The campaign began on November 29 1948, when the People's Liberation Army attacked Zhangjiakou, which changed the deployment of Nationalist Army as they sent the moblilized 35th Army to reinforce Zhangjiakou. The People's Liberation Army turned to strick Miyun shortly after, threaterning the city of Beiping. The Nationalists, being caught by surprise, shifted three armies from Tianjin to Beiping to improve the defense of the city, and ordered the 35th Army to return to Beiping. However, the 35th Army was cut off in Xinbaoan en route to Beiping. By now the People's Liberation Army had cut off the connection between Peking and Tianjian, and accomplished the encirclement against the above areas, which cut off the line of retreat for the Nationalists to the south and west. Although the nationalist regular force was caught by surprise, the nationalist intelligence organization made a swift response that almost changed the course of the war, and hence the nationalist fortune.

On December 7, 1948, Communist IV Field Army Headquarter was moved in Hebei. Nationalist undercover agents successfully by-passed the communist garrison and infiltrated into the Lin Biao's residence in the communist headquarter by night, and under the cover of darkness, managed to successfully kill Lin Biao's bodyguard. Hearing the gunshots, Lin Biao hide in the corner behind the door and prepared to ambush the nationalist agents should they enter his room, but the nationalist agents failed to realize what a big target they had stumbled on and retreated and thus narrowly missing Lin Biao. Lin Biao's secretary, living in the next courtyard, was the first one to reach Lin Biao's room after hearing the gunshots, and discovered Lin Biao was fine. Had the nationalist agents continued their attack, Lin Biao would certainly be killed, and the nationalist fortune at the least at the time, would be greatly changed, and so would the Chinese history.

After the 35th Army was encircled in Xinbaoan, the Nationalist troops in west of Peking launched desperate attack to west, hoping to remove the Communist encirclement on the 35th Army. But while in action, the Nationalist reinforcements were encircled as well. The 16th Army and five divisions from the 104th Army were all destroyed. The People's Liberation Army then launched Xinbaoan Campaign shortly after, captured the city the very next day and destroyed the 35th Army. On the 23rd, the Communist destroyed majority of 50,000 Nationalist forces that sallied out in northeast of Zhangjiakou.

Beginning in January 2 1949, the People's Liberation Army gathered up their offensive forces in Tianjin Campaign. The final attack was launched on January 14, and after 29 hours of intense action, the defenders 62nd Army and 86th Army, total up to ten divisions of 130,000 men were completely wiped out. The Tianjin garrison commander Chen Changjie was captured alive.

The Nationalist 17th Army Group and five divisions from the 87th Army in Tanggu retreated on January 17 via ocean.

After Tianjin had been captured by the Communists, the Nationalist defenders in Beiping were in a hopeless situation. Under immense pressure, Fu Zuoyi decided to negotiate with the People's Liberation Army for a peaceful settlement for the city. The 260,000 troops inside the city began to exit the city to the People's Liberation Army for reorganization. On January 31, the People's Liberation Army entered Beiping to take over. The Pingjin Campaign was over. Beiping, soon to be the capital of the new People's Republic of China, was renamed Beijing.