Phytophthora blight is one of the most serious threats to production of pumpkin in Guangxi province. It usually damages the stems and fruits and reduces the quality and yield of pumpkin. In this study,the causal organism of Phytophthora blight of pumpkin was isolated and cultivated. Its pathogenicity was also tested. Based on its morphological characteristics and ITS DNA sequences analysis,this pathogen was identified as Phytophthora capsici Leonian.