Abstract: The antifungal activity and efficacy of a novel quinoline compound ZJ5337 synthesized by Zhejiang Chemical Industry Institute Co. Ltd. was evaluated. In vitro, ZJ5337 at 10-20 mg/L showed high inhibition activity against the appressorium formation of Magnaporthe grisea. Greenhouse experiments showed that ZJ5337 at 50-100 mg/L exhibited high activity against the diseases caused by M. grisea and Sphaerotheca fuliginea with the efficacy greater than 80%. In addition, the duration of ZJ5337 was up to 15 days. ZJ5337 was unable to be transferred effectively between root and leaf, and among leaves of cucumber. The rain-wash test showed that rain-wash had significant impact on the efficacy of ZJ5337 within three hours, but not after 4 hours of the compound application. Field trials showed that 300-500 mg/L 2.5%ZJ5337 EC efficacy of 66%-91% against M. grisea and did not show any phytotoxic to the rice tested.