In 1927 Guan received a promotion as regiment commander of the General Headquarters of National Revolutionary Army, and was then transferred to the 11th division, one of Chiang Kai-shek's most elite units.

[citation needed] In 1933, Guan received orders from the nationalist government to help General Song Zheyuan defend North China against the Imperial Japanese Army led by Field Marshal Nobuyoshi Mutō in the Defense of the Great Wall.

In 1936, he led his unit into Shanxi province to help the local warlord Yan Xishan to drive away the communist troops commanded by his former classmate Lin Biao and was successful in his mission.

Guan defeated the communists in this campaign and Chiang Kai-shek promoted him to commander of the 52nd corps when the Second Sino-Japanese War broke out the next year.

Four days later, General Guan held a press conference and stated the government troops has the right to use force to quell the strike, and ordered the students to resume their classes.

But on December 1, 1945, Nationalist troops and student protestors clashed with each other and there were many casualties on both sides, Guan was made a scapegoat of the incident and resigned his command the next year.

In 1947, Guan succeeded President Chiang Kai-shek as commandant of the Whampoa Military Academy, and was appointed as deputy commander-in-chief of the Republic of China army.