Collect rhizosphere soil sample from 7 different region in China, then obtain 1700 rhizosphere bacteria through separate bacteria from different soil sample. In vitro, evaluate the bioactivity of rhizosphere bacteria against five varieties pathogenic bacteria. At last, we obtain 840 rhizosphere bacteria against pathogenic bacteria. Only 10% rhizosphere bacteria had bioactivity against all of the 5 pathogenic bacteria, the others had not the character. These 840 rhizosphere bacteria as resource, screen the bioactivity against the wheat powder mildew. The best control effect against the wheat powder mildew achieve 60%. Select the rhizosphere bacteria have bioactivity against patho- genic bacteria and the wheat powder mildew as farther research object.