xPythium species are among the agents of root-rot disease of bean plants, causing poor growth and yield. Identification and pathogenicity of Pythium species isolated from bean roots were investigated. P. ultimum was the most common species followed by P. sp. (HS- group). In the pathogenicity test, P. ultimum var. sporangiiferum caused severe damping-off on bean plants, while other species caused slight symptoms of root-rot and poor growth.