The CCP had long anticipated the attack of the Kuomintang army on Yan'an, and since the end of 1946, it has been arranged in many ways, "the first battle of the Northwest Battlefield: the battle of Xihuachi". However, the exact timing and deployment of the offensive depended on the already successful underground intelligence network at the time. Xiong Xianghui, who was praised by Zhou Enlai as one of the "last three masters" of intelligence work, mentioned in his memoirs that on the morning of March 2, 1947, Xiong was summoned by Hu Zongnan to his temporary office in Nanjing, told him that he was going to fight Yan'an, and handed Xiong two top-secret documents, one was the plan approved by Chiang Kai-shek to attack Yan'an, and the other was the deployment of the communist army in northern Shaanxi. That night, Xiong carefully read and memorized the copies of the two documents, and then burned the copies. The next day, after Xiong returned to Xi'an with Hu Zongnan and others, he reported the information to Wang Shijian, his liaison in Xi'an. On March 7, Xiong went to Wang Shijian again to inform him that the attack date had been postponed. Wang Shijian informed Xiong that he had submitted the battle plan to Yan'an, and received praise. When Xiong said that he could not continue to provide information because he had to go to Luochuan with Hu Zongnan, Wang Shi insisted that the strategic situation had been clarified and that the details could be checked by others. The data shows that in addition to Xiong Xianghui, the CCP also obtained news and intelligence from various other sources about the Kuomintang army's attack on Yan'an. More important ones include Cai Maolin, who was stationed in the Northwest Supply Area Headquarters, through Wang Chaobei, the Xi'an Intelligence Department of the Central Social Affairs Department, who provided the enemy's army number, troop station, commander's name, personnel establishment, and clothing supply plan of the current number; Mao Peichun (pseudonym Meng Xishan), who served as a special senior staff member at the Northwest Military Police Headquarters, provided the operational plan and troop deployment for attacking northern Shaanxi, including the number of troops participating in the battle, the number of troops, the address of the Luochuan secret service, and the security police force (see the humble article "Essays on Intelligence and Communications Work in the Northwest Battlefield in the War of Liberation"); The Kuomintang army's operational plan for attacking Yan'an was also reported by Wu Bochang of the Xi'an Intelligence Station to the Shaanxi Provincial Working Committee of the Communist Party of China with urgent information, and then reported to the forward headquarters by the provincial party committee's radio station.

According to the intelligence of various parties, on March 4, the War Department of the Military Commission counted and reported the strength of the Kuomintang army to attack Yan'an, and the four districts of Guanzhong, Longdong, Sanbian and Yulin had 7 divisions, 24 brigades, 52 regiments and 184,000 people of the regular army; There are 21 local teams with more than 10,000 people. There are 7 divisions, 24 brigades, and 73 regiments, with about 195,000 people. On 5 March, the War Department's "Battle Report" analyzed the dynamics of the Kuomintang army and determined that "the enemy is determined to attack Yan'an" and that "the offensive can begin after the reorganization of the 1st and 90th Divisions is completed." On 7 March, the War Department submitted the "Judgment Map of the Enemy's Attack on Yan'an" and the "Mileage Map of Yan'an South", judging that Hu Zongnan would attack north from the Yichuan and Luochuan lines with five integrated divisions.

The Kuomintang army launched an all-out attack on the Shaanxi-Gansu-Ningbo border region and seized Yan'an, with two original plans:

The first is to use Hu Zongnan Group from the southern route, Ningxia Ma Hongkui and Qinghai Ma Bufang Group from the western route, Fu Zuoyi and Deng Baoshan Group from the northern route, and the three routes to attack Yan'an; The Yan Xishan group was located on the east bank of the Yellow River to intercept and annihilate our army in one fell swoop. In the other case, Ma Hongkui, Ma Bufang, and Deng Baoshan's clique were used to contain and cooperate on the western and northern fronts, concentrate the Hu Zongnan clique to break through from the southern front, capture Yan'an, annihilate our army in the border area, or expel our army to cross the Yellow River in the east or go north to the Suimeng desert.

According to our army's analysis, the concentration of troops in the first case will narrow our army's room for maneuver and increase our army's operational difficulties. However, it was difficult for Fu Zuoyi to draw troops from afar, Yan Xishan was too busy to take care of himself, and Qingning Erma and Deng Baoshan were not only afraid that Hu Zongnan would take the opportunity to eliminate the "miscellaneous cards", but also afraid of being annihilated by our army, and each tried to preserve its strength; On the one hand, Hu Zongnan was confident that the superiority of troops was enough to capture Yan'an, but on the other hand, he was afraid that Erma would seize Yan'an, take away its merits and take the opportunity to develop to Shaanxi. Therefore, Hu, Ma, and Deng actually have different aspirations. Therefore, our army estimates that although there is a possibility that the enemy will block the enemy from the east and attack on the other three sides at the same time, there are contradictions between the Hu, Ma, and Deng groups, and there is a huge disparity in the number of troops on the three sides, so this possibility is very small. Judging by the enemy's situation and terrain at that time, our army must take the southern front as the main direction of attack.

On 28 February, Hu Zongnan and Chief of Staff Sheng Wen went to Nanjing to meet Chiang Kai-shek, and when Chiang Kai-shek asked him about his grasp of the operation in northern Shaanxi, Hu Zongnan listed the comparison of forces and said that he was "extremely sure." At the dinner table that night, Chiang Kai-shek again asked Hu Zongnan if he was sure, but Hu Zongnan still insisted on his original statement. On March 1, both the Ministry of Defense and Chiang Kai-shek agreed to his plan to attack Yan'an.

Not only was the main direction of the Kuomintang's campaign expected by the Chinese Communists, but also the specific offensive line, that is, along the Xianyu Highway and its main assault directions in the Dongyun County and Linzhen areas, was also expected by our army. This is because:

1. This direction is a shortcut to attack Yan'an, and according to the itinerary, Yan'an can be reached in one day and night;

2. There is a Yellow River barrier on the right flank, which can avoid our army in the southwest of Shanxi Province from hitting its flank, and at the same time, there are Xianyu highway transportation trunk lines and highways from Luochuan to Yichuan, Xi'an from Chengxian to Yichuan, Xi'an through Dali, Hancheng to Yichuan and other highways as branch lines, and the rear transportation is convenient. The area south of Yan'an, east of Xianyu Highway, is a slightly forested mountainous area, but there are major roads connecting between Juxian, Niuwu, Nanniwan and Yichuan, Linzhen, Nanniwan and Yan'an. The area west of Xianyu Highway is dense with mountains and forests, and the traffic is inconvenient, with many cross-section ditches, and the road is far away, and the supply is inconvenient;

3. The Kuomintang planned to attack Yan'an several times in the past, but they all took this as the direction of the assault.

The Kuomintang had a total of 43 brigades and 320,000 troops in the northwest. In addition to the 70,000 men of the 9 brigades garrisoning Xinjiang, a total of 250,000 men of the 34 brigades were used to attack the Shaanxi-Gansu-Ningbo border region. Among them, Chiang Kai-shek's descendants are more than 170,000 people in 20 brigades of the Hu Zongnan Group of the Xi'an Sui Administration; There are 69,000 people in 12 brigades of Zhang Zhizhong, Ma Bufang, and Ma Hongkui Group in the northwest, and 12,000 people in 2 brigades of Deng Baoshan Group. At that time, the War Department of the Military Commission probably correctly judged that the Liangma Group would not quickly join the battle to attack Yan'an[4], so it did not include the troops in the northwest. In detail, the total strength of Hu Zongnan's group is 171,700 people, including the integrated First Army (75,000 people), the integrated 29th Army (73,000 people), the 135th Brigade of the 15th Division (4,700 people), the 55th Brigade of the 38th Division (7,000 people), and the 10th Division (including the 10th Brigade and the 85th Brigade with a total of 12,000 people), of which the integrated First Army includes the integrated 1st Division (1st Brigade, 78th Brigade, 167th Brigade, a total of 28,000 people), the 27th Division (31st Brigade, 47th Brigade, A total of 27,000 people), the 90th Division (53rd Brigade, 61st Brigade, a total of 20,000 people), the 29th Army including the 17th Division (48th Brigade, 12th Brigade, 84th Brigade, a total of 17,000 people), the 36th Division (123rd Brigade, 165th Brigade, 28th Brigade, a total of 33,000 people), and the 76th Division (24th Brigade, 144th Brigade, New 1st Brigade, a total of 23,000 people). The 22nd Army (86th Division, New 11th Brigade) of Deng Baoshan Group has a total of 12,000 people. There are about 184,000 people in the Hu and Deng groups, plus more than 10,000 people in the local team of the Kuomintang, totaling 195,000 people.

According to Ren Zixun, deputy commander of the 90th Division of the First Army, by 10 March, there were 7 integrated brigades of the 29th Army, including the 36th Division (123rd Brigade and 165th Brigade), the 76th Division (24th Brigade and 135th Brigade), and the 17th Division (12th Brigade, 48th Brigade, and 84th Brigade) of the 29th Army. Assembled near Yichuan, there were seven integrated brigades, including the 1st Division (1st Brigade, 78th Brigade, and 167th Brigade), the 27th Division (31st Brigade, 47th Brigade), and the 90th Division (53rd Brigade and 61st Brigade). In addition, the entire 144th Brigade is still assembled near Tongguan and is on standby. There are 6 divisions and 15 brigades, with a total of about 150,000 men. The number of divisions and brigades is basically the same as the recollection of Shen Ce, who was the commander of the entire 78th Brigade at the time, but Shen Ce believes that the total strength of the troops is "about 105,000 in total", because "at that time, after all kinds of battles and long-distance marches, as well as long-term corruption and short-term occupation of troops at all levels, the actual number of soldiers could not be accurately counted, and the figures cited were estimates based on the actual situation." Shen Ce's estimate does not include "the soldiers of the logistics and transportation units under the jurisdiction of the Seventh Supply Zone stationed in Xi'an, as well as special forces such as engineers, armored troops, chariot troops, artillery, and signal troops, which are directly under the command of the First Theater."

In addition to eating vacancies, because the Kuomintang army needed to divide troops to occupy important places and protect communication lines, the gap in strength between the troops on the front line became smaller. According to Hu Zongnan's estimates, there are 12 brigades and 84,000 troops on the front line that can be used for attack, and the actual number of people actually engaged in combat may be even smaller.

The CCP's judgment on the strength of Chiang's army attacking Yan'an is basically in line with reality. On March 17, it was thought that the main force of Chiang's army attacking Yan'an consisted of 9 brigades, but by the 19th, it had been ascertained that its total strength was "a total of 7 divisions, 14 brigades, 34 regiments, and 150,000 men."

Hu Zongnan's "study" said: "The bandits' regular troops in northern Shaanxi include about 60,000 people from the 8th, 10th, and 39th brigades, the 1st, 2nd, 3rd, 4th, and 11th garrison brigades, the 1st independent brigade, and the 6th Cavalry Division; 7,000 people from the 358th and 359th brigades of the bandit Wang Zhen's subordinate unit have been transferred back from western Shanxi; about 15,000 people from the 10th, 11th, 12th, and 24th brigades of Chen Geng's subordinate department; about 10,000 people have been trained in the three brigades of He Long's subordinate department, and about 70,000 militiamen have been trained, totaling 160,000 people." The confusion of the numbers listed in this statement is not difficult for those who have a little knowledge of the history of the war between the Kuomintang and the Communist Party to notice. According to the recollections of personnel of the Kuomintang Air Force, the information obtained by the Air Force Operations Section from the Intelligence Section was that the communist army in northern Shaanxi had 13 brigades and three divisions, totaling about 100,000 people. According to a careful investigation of the number of divisions and brigades, we learned that the numbers of the field troops in the Shaanxi-Gansu-Ningbo Border Region judged by the Kuomintang army at that time were: 120th Division, 27th Division, 358th Brigade, 359th Brigade, New 1st Brigade, New 4th Brigade, New 8th Brigade, New 9th Brigade, New 11th Brigade, 1st, 2nd, 3rd, and 4th Garrison Brigades, and 6th Cavalry Division, totaling more than 70,000 men. In addition, there are more than 90,000 military regions and militia troops.