Dishui Lake(DSL) has received a great deal of attention since it built, there are many researches on the quality of water in it, but the research on the bacterial diversity overall was insufficient. Therefore, this study combined 16S rRNA gene denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene metagenome and bioinformatic analysis to understand bacterial diversity and community structure in surface water of DSL, including water fecal pollution indicator bacteria, water eutrophication typical bacteria, pathogens and conditional pathogens. The results show that:bacterial diversity in these 5 water samples can represent it in surface water of DSL at sampling time. 428 OTUs have been clustered from 5 DSL water samples and belong to 17 phyla, 39 classes, 66 orders, 130 families, 191 genera and 282 species. Actinobacteria, Cyanobacteria, Proteobacteria, Bacteroidetes, Verrucomicrobia and Planctomycetes are six dominant phyla in these 5 samples and account for 97% of total bacterial sequences in these samples. Except for a few sequences of Shigella (0.1%), sequences of water fecal pollution indicator bacteria, Pathogens and conditional pathogens were not found in metagenome. In conclusion, the characteristics of bacterial diversity in surface waters of DSL are similar to those of typical freshwater lakes and there are no water-contaminating bacteria detected in the lake, and there is no tendency that blue algae will cause blooms.