Purple nonsulfur bacteria are one branch of purple phototrophic bacteria, which are ecologically important and have valuable applications. In this study, we established paraffin wax overlay plate method for the isolation and the enumeration of purple nonsulfur bacteria. Compared with several tra-ditional methods, the new one was found to be more rapid and convenient. We applied this method to-gether with molecular approaches to investigate purple nonsulfur bacteria in paddy soil, and found that it can well reveal the diversity of purple nonsulfur bacteria at culturable level, when formate acts as carbon source. We believe the new method would be of great help to the investigation of purple non-sulfur bacteria in environment.