Abstract: To understand the optimal condition for the development and germination of conidium in mung bean leaf spot caused by the Cercospora canescens, nine culture media and different culture conditions were studied. The results showed that Cercospora canescens could be sporulated in sorghum grain culture medium at 25℃ with 10 days post incubation (dpi). The amount of conidium sporulated could reach 9×105 conidium/mL at 14 dpi. There was less production of conidia with corn meal and wheat grain media, whereas no sporulation with other media. Additionally, a suitable condition for conidia germination was 25℃, pH 6-7 under dark condition, where germination rate could reach 76.0% after 20 h incubation, and there were significant differences in germination rates among different light and temperature conditions. In sucrose and peptone media, the conidia germination ratio was 87.0% and 86.3% , respectively. The optimal condition for sporulation of Cercospora canescens was at 25℃ on sorghum grain culture medium, and the optimal condition for spore germination was 25℃, pH 6-7 in darkness. Conidia germination radio could be mildly improved with the addition of sucrose and peptone.