Abstract:Abstract: [Objective] To understand the microbial community in mangrove sediments. [Methods] Sixteen stations were established in the Fugong mangrove area of Jiulong River Estuary, Fujian, China. Microbial community structure in this area was evaluated by PCR-DGGE method. The genetic diversity of microorganisms was analyzed based on the DGGE fingerprint. [Results] There were significant differences among the Shannon-wiener index, Richness and evenness. The possible reason might due to distinct location of samples from different stations. Bacterial diversity was higher in the mangrove areas than that in non-mangrove areas. Similarity analysis of bacterial communities in different station showed certain trends in similarity coefficients, and bacterial community structure similarity of the same transect was much higher than others. According to the results of sequence analysis of DGGE dominant bands, all of them were phylogenetically close to Proteobacteria, Acidobacteria and Chlorobia which belonged to uncultured microbes from coastal sediments in the estuary. [Conclusion] There are abundant microbial diversity and a large number of unknown microbial resources in mangrove sediments which need further research.