Wu was born in Jiujiang, Jiangxi Province, and grew up in Yangzhou, Jiangsu Province. He graduated from Tsinghua University in 1937. From 1940 to 1942, he pursued his postgraduate study at Peking University, under supervision of Zhang Jingyue, then chair of the department of Biology at PKU. In 1950, Wu became a research fellow and vice Director of the Botanical Institute of CAS. He was elected an academician of CAS in 1955. Wu was appointed as the Director of Kunming Botanical Institute of CAS in 1958.
On January 8, 2008, Wu received the prestigious State Preeminent Science and Technology Award for 2007, the highest scientific prize awarded in China.