Denaturing gradient gel electrophoresis (DGGE) can describe microbial communities based on partial sequences of nucleic acid and monitor uncultured bacterium and it's functional genes. It is well-established molecular tools in microbial molecular ecology that allows the study of diversity and dynamics of microbial communities. Here, common issues in the analyses of microbial community by DGGE were raised, and the feasible resolving methods were introduced in this paper. The effects of samples pretreatment and PCR amplification on DGGE analysis were evaluated. Optimization and statistical analysis of DGGE profiles were discussed. Finally, prospect of DGGE for understanding microbial communities were reviewed.