A new fungal disease in orchid plants was discovered recently at Wutong Shan Orichid Nurseries Shenzhen, Guangdong province. The fungus produced new spots on orchid leaves in the middle of Fberary, and the disease epidemic peak occured from April to June when the cloudy and damp weather continuously existed. The disease was more serious if orchid plants were cultivated under windless and hot condition. After following Koch's postulation and comparative inoculation test, the pathogen was identified as Stagonospora curtisii Sacc.. A detailed description of the pathogen and symptoms were given in this paper. In addition, the biological characters of the pathogen, and the inhibting effect of 12 bactericides on germination were tested respectively. The pathogen was reported in orchid plants for the fist time.