The bacterial strain Pa608 was isolated and screened from the inter-rhizosphere soil of healthy plants collected from fields with severe pepper blight damage, and was identified as Pseudomonas aeruginosa through colony morphology, molecular homology and its physiological, biochemical and extracellular enzyme-producing characteristics. The antimicrobial spectrum of Pseudomonas aeruginosa was tested by the plate standoff method, and the efficacy of the antimicrobial spectrum was determined in pot tests, and then applied to greenhouse pepper fields to test its greenhouse efficacy. It is found that the strain has good antagonistic effect on Botrytis cinerea, Pyricularia oryzae, Phytophthora capsici, Bacillus anthracis, etc. The efficacy was 88.00% in potted plants at a concentration of 1.0×109 cfu/mL, pouring 3 mL/pot, and the efficacy was 74.96% in conservatories at the tenfold dilution of the bacterial solution and pouring 50 mL/plant.