Meadow moth(Loxostege sticticalis L.) is a major migratory pest in northern China, and its larvae can cause severe damage to a wide range of crops. To determine the threshold for controlling meadow moth in adzuki bean fields, field inoculation experiments were conducted in Gongzhuling City, Jilin Province. The relationship between larval density and yield loss of adzuki bean was analyzed. The results showed a significant positive correlation between yield loss rate(y) and larval density(x), which could be described by the regression model y = 10.658x-4.799(R²=0.985 7). Based on a comprehensive analysis of current production costs, market prices, and the costs and benefits of meadow moth control in adzuki bean cultivation, the control threshold for meadow moth in adzuki bean fields in Jilin Province was determined to be 1.04 larvae per plant. This threshold provides a scientific basis for the effective and rational control of meadow moth in adzuki bean fields.