Penicillin is one of the greatest medical discoveries in the 20th century.In 1929,Alexander Fleming,who was a bacteriologist working in London,accidentally discovered from a contaminated Petri dish that the secretion of a greenish mold,Penicilliumnotatum,could inhibit and kill Gram positive bacteria.From 1940 onwards,scientists at Oxford University,notably Howard W.Florey and Ernst Chain,devoted their energy to the extracting,purification and clinical treatment of penicillin and later carried the serial technology to the United States to seek for cooperation in its pharmaceutical production.During the WWⅡ,with the help of agencies of the American government,some research institutes and pharmaceutical enterprises formed a close affiliation for the improvement of the relative technologies to enable an industrial production,in which process new techniques such as submerged fermentation were adopted.Mass-producted penicillin played a significant role by the end of the war.At the same time,the National Epidemics Prevention Bureau (NEPB) of China,being temporarily stationed in Yunnan Province in wartime,started China’s own study of penicillin.Leading by a famous microbiologist,Tang Feifan,researchers Zhu Jiming,Huang Youwei and Fan Qingsheng completed the whole flow of experimental work from selecting strains to harvesting the production.Despite being short of facilities and equipment,they obtained a lot of positive results at the end of the war.This paper tries to summarize and discuss briefly the work on penicillin in China during that hard time.