The pathogen that causes strawberry brown bloth disease was identified and proved through a procedure of Koch’s postulation. Pycnidium and conidia were produced in the diseased leaves and PDA medium. The pycnidium was spherical and black. The conidiophores were branching. The conidia was oval or spindle shaped, transparent and single-celled, with the size of (5.7-7.3) mm×(2.0-3.0) mm.Based on the morphological characteristics of conidia and its DNA, the pathogen was identified as Pho-mopsis obscurans (Ellis & Everh.) B.Sutton. The effects of temperature, pH value and other environmental factors on the pathogen growth and sporulation were studied. The result showed that the optimum temperature was 25-30 ℃ and the optimum pH value was 6, and light will promote its mycelial growth and sporulation.