43 cultivated strains and 11 wild strains of Pleurotus ostreatus were used as materials,by adopting copulative methods of antagonistic test and ITS sequence analysis,the genetic diversity of the tested strains were analyzed.The results showed that the antagonistic test results were significantly different among the strains with larger color differences,so the 54 strains were divided into 32 different strains by antagonistic method.According to the results of ITS sequence analysis and constructed phylogenetic tree,they were grouped into two categories,and the two categories had relatively distant genetic relation and independent evolution,as a result,they were identified as 36 strains.The antagonistic test results were basically consistent with ITS sequence analysis,except for the antagonistic group Ⅵ—Ⅸ.Above all,the combination of antagonistic test and ITS sequence analysis method can be used as a means of strain identification.