Abstract: Isolated microspores of eighty early and middle cauliflower cultivars were cultured.The main factors affecting the embryo induction of the microspore were studied.The results showed that embryoids had been obtained from twenty cultivars, the inducement ratio was up to 25%.It was advantage for microspore survival in the medium with 16%sucrose.The optimal concentration of sucrose for microspore development was 13%.When adding liquid to the medium during the culture, the embryo yield could be significantly improved.The optimum donators for isolated-microspore culture were the buds selected in the prophase to medial phase of full bloom and the microspore selected at the late uninucleate stage to binueleate stage at 10—20℃within six days, after the heat-shock treatment at 33℃for 48h and continued culture in darkness, the embryo yield was the highest.