Abstract: Systematical observations and researches were conducted on the population size dynamics of Apis mellifera Ligustica Spi. and Apis cerana cerana Feb. in Wanzhong,Wanxi and Wannan mountainous area in Anhui Province in1997～1999. The results showed that the bee population size was influenced by climate and flower fertility,which was higher in Spring and Autumn,and lower in Summer and Winter. The propagation and renewal of A. mellifera in Autumn were quicker than those of A. cerana cerana,while the effect of overcoming Summer was inferior to that of Apis cerana cerana. The sex ratio of A. mellifera was (314.4±289.9):1～(329.4±305.8):1,and that of A. cerana cerana was (334.2±235.5):1～(413.1±3772):1. The birth of drones was seasonal,and the age structure of each bee population was variable.