Born Hu Hongzhi (洪騂 hong2 xing1) in Shanghai to Hu Chuan (胡傳, courtesy name Tiehua (鐵花)) and Feng Shundi (馮順弟), Hu had an ancestry in Jixi (績溪), Anhui. In January 1904, he was arranged to marry Jiang Dongxiu (江冬秀), an illiterate girl one year older than him with bound feet, and who Hu married in December 1917. He received his fundamental education in Jixi and Shanghai.
Being one of the national scholarship, on August 16, 1910, Hu was sent to study in Cornell University in the United States and later Columbia University. He was greatly influenced by his professor, John Dewey, and became a lifelong advocate of pragmatic evolutionary change. He started to write for New Youths from 1917, and quickly gained much attention and influenced many people. He got his Ph.D on philosophy in 1917 and went back to lecture in Peking University. Being the editor of the New Youth, Hu became one of the leading and influential intellectual during the May Fourth Movement and later New Culture Movement. He quit New Youth in the 1920s and published several political newspapers and journals with his friends. His most important contribution was promotion of vernacular literature (Baihua) in replace of classic literature (see Classical Chinese). He was ambassador of Republic of China to the United States of America (1938-1942), chancellor of Peking University (1946-1948), and after 1958 president of the Academia Sinica in Taiwan, where he remained until his death by heart attack in Nangang at the age of 71.