To review the studies on the etiology of trachoma and to honor Professor Tang Feifan (Prof FF Tang) He is the first scientist who was successful in isolating and cultivating chlamydia trachomatis in 1946 Data sources The principal literatures are cited from Tang’s papers published from the 1930s to the 1950s Earlier literatures concerning early hypotheses for trachoma pathogenic agent are also studied Study selection and data extraction Only important and conclusive breakthroughs in Tang’s papers are selected and extracted Results and conclusions In the 1930s Tang was intending to repeat Noguchi’s experiments in isolating bacterium granulosis from cases of trachoma in China and to employ bacterium granulosis isolated by Noguchi in 1928 for reproducing experimental trachomatous human clinical manifestations in China Both experiments showed negative results In the 1950s, before isolated chlamydia trachomtas, Tang and his colleagues had finished two fundamental studies: (1) the histological nature of trachoma, their relationship to etiological agent as well as to the host cells; and (2) the clinical manifestations and the morphological pictures of trachoma in monkeys Eventually chlamydia trachomatis was isolated successfully and cultivated continuously To review the studies on the etiology of trachoma and to honor Professor Tang Feifan (Prof FF Tang) He is the first scientist who was successful in isolating and cultivating chlamydia trachomatis in 1946 Data sources The principal literatures are cited from Tang’s papers published from the 1930s to the 1950s Earlier literatures are also studied Study selection and data extraction Only important and conclusive breakthroughs in Tang’s papers are selected and ended Results and conclusions In the 1930s Tang was intending to repeat Noguchi’s experiments in isolating bacterium granulosis from cases of trachoma in China and to employ bacterium granulosis isolated by Noguchi in 1928 for reproducing experimental trachomatous human clinical manifestations in China Both experiments for negative results In the 1950s, before isolated chlamydia trachomtas, Tang and his colleagues had finished two fundamental studies: (1 ) the histological nature of trachoma, their relationship to etiological agent as well as to the host cells; and (2) the clinical manifestations and the morphological pictures of trachoma in monkeys Eventually chlamydia trachomatis was isolated successfully and cultivated continuously