In 1916, Zhu Ziqing graduated from Secondary school and entered Peking University. A year later, he changed his name from Zihua to Ziqing, the name change was said to be due to his family's dire economic conditions. Zhu Ziqing graduated in 1920, and went to various secondary schools in Hangzhou, Yangzhou, Shanghai and Ningbo to teach. During his time as a teacher, he was also active in the poetry circles, and became a well-known poet.
Later, Zhu Ziqing was appointed professor of Chinese Literature at Tsinghua University in 1925, and on August 1928, he published his first essay collection known as "Retreating Figure". From 1931 to 1932 he studied English Literature and Linguistics in London. In 1937, when the Second Sino-Japanese War broke out, he followed his university to move to Changsha, Kunming and Chengdu. During this time, Zhu Ziqing continued to teach in other universities.
After the Second World War, Zhu Ziqing encouraged his students in Kunming to oppose Chiang Kai-shek for starting the Chinese Civil War. In 1946, he returned to Beijing and was appointed the Head of the Chinese Language Department in Tsinghua University. When he heard of the assassination of patriotic authors Li Gongpu and Wen Yiduo, he disregarded his own safety to attend the funeral of both men.
Zhu Ziqing later died on August 12, 1948 after joining the rebellion of refusing aid from the United States. Though it is a common belief that Zhu died of starvation due to Mao Zedong's famous article "Farewell, Leighton Stuart". However, the real cause of Zhu's death was gastric perforation resulting from his severe stomach ulcers.
When Zhu Ziqing entered Peking University, he fell in love and married Wu Zhongqian (武仲谦). Zhu's wife soon died and he married his second wife Chen Zhuyin.