Abstract: A field effect experiment on the Peach Brown Spot (PBS) was conducted. Its results show that the effects of 250 g/L Hexaconazole SC of 3000 times, 4000 times, and 5000 times were higher than Mancozeb with significant difference. Hexaconazole Suspension of 3000 times and 4000 times were higher than 90% in prevention effect with no significant difference. The results also showed that Hexaconazole SC had good effect in preventing peach from PBS, and could be safely used in florescence and infant fruiting period with no pollution peach fruit surface. In all Hexaconazole SC was an ideal pharmacy of controlling PBS by enhancing peach leaf photosynthesis.