Abstract: Risk assessment was conducted for operators in strawberry greenhouses during pesticide application and harvest. Chlorothalonil (75%, WP) was applied by using a manual knapsack sprayer. Dermal patch method was used to measure potential dermal exposure (PDE). During the application of chlorothalonil in the strawberry greenhouse, the rate of potential dermal exposure of applicators ranged from 19.2-46.6 mL/h with average of 30.2 mL/h. It's also found that the major exposure part was lower legs. During the harvest, the rate of potential dermal exposure of harvesters at the first day was 3.8 mL/h, but at the seventh day it was only 0.027 mL/h. Further, the major exposure part was hands during harvest. The margin of safety (MOS) was calculated. For applicators, MOS was 0.258 indicating risky environmental conditions, but the MOS was greater than 1 for harvesters during each day of harvest process (1-7 days), which indicated safe working conditions for harvesters. Chlorothalonil applied in the strawberry greenhouse could put applicators in risky working conditions, but the harvesters are relatively safe. Therefore, applicators should strengthen personal protection or shorten exposure time, and harvesters should pay attention to hand protection in the strawberry greenhouse.