Abstract:Polymerase chain reaction (PCR) amplification of a portion of a gene encoding a surface protein of Wolbachia (wsp) was used to detect the Wolbachia infection of the population of Pteromalus puparum and Nasonia vitripennis by universal primers of wsp gene and the specific primers for wsp genes of A and B Wolbachia supergroup. The PCR products were cloned, sequenced and analysed. The results demonstrated that both species were infected with strains of A and B Wolbachia, and wsp gene sequences of females and males from the same wasp were identical. By a pair of universal primers, a region of 540 bp of Wolbachia wsp gene were amplified from both of P.puparum females and males, likewise a region of 558 bp from N.vitripennis. The strains of Wolbachia, which infected P.puparum and N.vitripennis, were classified as the Pip group of B-Wolbachia and Uni group of A-Wolbachia, respectively. Both 548 bp regions of A-Wolbachia were amplified from these two wasps, and the sequence percent identity was 99.8%. In contrast, the 424 bp and 439 bp regions of B-Wolbachia were respectively amplified from P.puparum and N.vitripennis, and their sequence percent identity was 87.5%.