Abstract: Composition and predominant groups of the bacterial community in Lake Zouhai in the city of Fuzhou were determined and analyzed by using PCR-DGGE. Water samples were collected from 4 sites each time in December 2011, February 2012, April 2012, and June 2012. The results showed that the water samples from the different sites on a same date had a similar bacterial composition, while the numbers and positions of DGGE profiles indicated significant compositional differences on different dates. Twenty DGGE bands with varied phylotypes were excised, cloned, sequenced, and analyzed to show 11 of them having possible affiliations with Proteobacteria, 5 with Bacteroidetes, two with Actinobacteria, and two with Cyanobacteria. Analysis on the bacterial compositions suggested that Proteobacteria was the predominant group existed in the lake.