Abstract:The Bayes method sampling plan of water saving irrigation products was established by using the prior data and experiment. The Bayes sampling plan results of plastic pipes, microirrigation emitters and rotating sprinkler were collected and showed the sample decrease ratio E mainly had a relationship with prior product qualified ratio variance S2R and average Ra. In normal lot it was less than 1200, if S2R=0.002 and Ra=0.95, sample decrease ratio of plastic pipes and micro-irrigation emitters was higher than 62%, also sample decrease ratio of rotating sprinkler was higher than 85%. Compared with normal sampling plan, the Bayes sampling plan could reduce the sampling number more than 20% in the condition of same inspection effect; therefore the Bayes sampling plan reached the purpose of reducing the sampling number, lowering the inspection cost and increasing the inspection benefit.