To improve the accuracy of aerobic plate count in food,7 groups of laboratory te chnicians tested the samples with the same amount of bacterium simultaneously.Th e result that 3 laboratory technicians made aerobic plate count to the same lot of samples was contrasted,laboratory technicians repeatedly added samples in the same plate and tested them.The results were analysed by statistics methods sepa rately.The results show that homogeneity of samples,correct determine of control range of reading errors and correct estimation of bacterium account are element s that affect accuracy of aerobic plate count. Author's address:Cheng Suyun,Center of Disease Prevention and Contro l of Zhejinang Province,Hangzhou,310009,PRC.