Abstract: 【Objective】 To clarify the species and taxonomic status of a rare fungus from grapevine diseased leaves in Turpan region of Xinjiang. 【Methods】 Culture traits were observed in the strains and the size of primary and secondary conidia were measured.Based on ITS and LSU sequences, phylogenetic tree was constructed by Maximum likelihood, the maximum parsimony method and Bayesian method.Meanwhile, the purified strain was cultured to different levels of four factors, such as different medium types, light conditions, pH and culture temperature, and combined orthogonal experiment were conducted to explore the optimum growth conditions. 【Results】 The results showed that the interaction of four factors, including medium species, light conditions, pH values and culture temperature, was found to have a significant effect on strain Pt4-1and the strain grew faster on PDA, SDA medium than on CMA medium.The growth rate of strain Pt4-1 grew the fastest under SDA medium, semi-light, pH 5 and temperature 25 ℃, with the average growth rate of 2.29 cm/d.The growth rate of strain Pt4-1 was the weakest under CMA medium, half-light, pH 5 and temperature 25 ℃, the average growth rate was 0.55 cm/d. 【Conclusion】 After comprehensive analysis, Pt4-1 was identified as Quambalaria cyanescens.Mixed orthogonal tests indicated that the growth rate of strain Pt4-1 was faster on PDA and SDA media than that on CMA medium and could secret purple pigment, but no purple pigment on CMA medium.With the increase of culture temperature, the secretion of pigment decreased.