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Verticillium wilt of sunflower occurred much popular in China, it caused severe yield loss of sunflower.Knowledge on the genetic diversity of sunflower Verticillium dahliae is lack.In order to control sunflower Verticillium wilt efficiently, the genetic relationships among 36 V.dahliae isolates collected from five different provinces in China and identified with ITS1/4 primers.The complete intergenic spacer (IGS) region of the nuclear ribosomal RNA gene was amplified and sequenced.Using the maximum-likelihood distance, the sequence of the complete IGS region were used to analysis the genetic relationships among of all tested sunflower V.dahliae isolates.Phylogenetic analyses data set sequences into three distinct groups.Within the three groups, the first two groups only have three strains, and the rest of seventy-seven strains formed the third group indicting less variation among sunflower V.dahliae isolates.We also detected the vegetative compatible groups (VCG) of the collected V.dahliae isolates using nitrate non-utilizing method, 33 isolates belong to VCG6 and just 3 isolates is VCG2B.Using published specific primer of V.dahliae Racel and Race2, we detected race composition within 36 sunflower V.dahliae isolates from 10 different regions in China, all tested isolates belong to race 2.