Abstract: Study on occurrence period and variety natural disease resistance of strawberry powdery mildew in greenhouses, The results indicate that strawberry powdery mildew occurred is general on leaf in February to March, disease becomes aggravated in April, and the highest could reach in May. Results also showed that disease occurrence was milder on fruit before March, and disease condition becomes more serious after April. The high resistance, resistant, susceptible, highly susceptible were 8, 5, 3 and 3 of 19 strawberry varieties, there was obvious resistance difference between cultivars. Study on screening out fungicides proved that the effect of nine fungicides such as difenoconazole and hexaconazole was above 80%, had a better effect on strawberry powdery mildew.