The seasonal changes of bacteria community composition in digestive diverticula of 2 age scallopsChlamys farreri were studied.The scallop samples were collected every month since June 2009 to June 2010(except Feb.)from Shazikou Liuqinghe sea area of Qingdao,which was the scallop culture area.The genomic DNA was extracted from digestive diverticula of scallop using SDS schizolysis method.Bacterial V3-V5 region of 16S rDNA was amplified with the 358f and 907r primers.Then,denaturing gradient gel electrophoresis(DGGE)was used to analyze and discriminate the amplified fragments.The DGGE fingerprint was analyzed by software Quantity One.The results showed that DGGE profiles exhibited 11 distinguishable bands,and 9 bands existed in all 12 months,the proportion of co-existed bands was 81.82%,the results indicated that the bacterial community composition was relatively stable in the digestive diverticula.Only 9 DGGE bands were successfully re-amplified,cloned,sequenced and aligned with BLAST.The result showed that the bacterial sequences shared high similarities(97%-99%)with sequences logged on NCBI.And the 9 bands belong to 4 major groups:Proteobacteria,Firmicute,Cyanobacteria and Actinobacteria.The predominant bacteria species in digestive diverticula of scallops were Massilia,Bacillus,Synechococcus,Exiguobacterium,Rhodococcus and uncultured bacteria.