Objective To study the molecular epidemiologic characterization of P.pneumotropica. Methods A randomly amplified polymorphic DNA polymerase chain reaction assay (RAPD-PCR) was used to genetically characterize and differentiate 15 isolate strains and a laboratory reference strain of P. Pneumotropica. Results 16 isolate strains yielded 4 RAPD profiles, with the same genotype between common vole and several mice isolate strains. Conclusion The distinct DNA polymorphism of P.Pneumotropica was found; Common vole was probably one of infection sources of P.Pneumotropica in laboratory animals.