Seeds are regarded as a potential reservoir and carrier for beneficial microbes.Compared to rhizosphere andphyllosphere，seed-associated bacteria remain largelyunrealized.In this study we investigated the rice seed endophytic bacteria of long term rotations of rice-rice-milk vetch(R -R-MV)and rice -rice-winter fallow(R -R-WF)using cultivation -dependent method and functional plate assays，with the aim of assessing the composition，function and the effects ofgreen manure rotation on the rice seed endophytic bacteria.The bacterial population in rice seeds of the R -R-MV rotation was significiant higher than that of R-R-WF.The composition of seed endophytic bacteria was significantly changed after long-term green manurerotation.At genuslevel， Pseudomonas and Xanthomonas were the largest groups in R-R-WF，accounting for 28.57% and26.19%. Pantoea was the most dominant genus in R-R-MV，accounting for27.94%，followed by Pseudomonas(14.71%)and Paenibacillus(13.24%).Most of isolates had plant -beneficialcharacteristics，indicatingtheir close relationships withplants.The plant beneficial resources obtained in this study will contribute to the research and application of seed endophytes as bioinoculants in sustainable agriculture.