Botryosphaeria dothidea is an important pathogen of a wide range of hosts.Although the sexual stage of B.dothidea was found to be widely distributed on a recent survey of the major apple production areas in China, the nature of its sexual reproduction is still unknown.Using genomic data of B.dothidea, primers targeted on the MAT1-1 and MAT1-2 idiomorphs were designed, respectively, and used to amplify the MAT1-1-1 and MAT1-2-1 genes.A sequence containing an open reading frame (ORF) that encoded a protein with an alpha-box and a sequence containing an ORF that encoded a conserved high-mobility group (HMG) box were yielded.