Silkworm (Bombyx mori) is an economically important insect and an ideal nontarget organism to study the environmental assessment of pesticides. Two acute toxicity test methods, leaf-dipping and quantitative spraying, with five insecticides, were compared for pesticide risk assessment. Based on LC₅₀ values of these insecticides by both methods, the order of toxicity levels of five insecticides tested against silkworm was as follows: emamectin benzoate>lambda-cyhalothrin>imidacloprid>chlorpyrifos>dimethoate. Means of relative confidence interval values for individual insecticides of leaf-dipping and quantitative spraying method were—emamectin benzoate (22.55 and 19.03%), lambda-cyhalothrin (18.03 and 17.71%), imidacloprid (19.21 and 16.96%), chlorpyrifos (17.20 and 15.97%), and dimethoate (17.78 and 15.81%). The coefficient of variation values were—emamectin benzoate (17.74 and 5.44%), lambda-cyhalothrin (21.15 and 5.16%), imidacloprid (13.01 and 5.65%), chlorpyrifos (16.72 and 4.85%), and dimethoate (28.36 and 7.93%). The results of the study show that the quantitative spraying method is more effective than the leaf-dipping method in precision and reproducibility. The results of this study will offer a useful reference for selecting a more scientific and rational method for pesticide risk assessment.