Abstract: By using the standard test methods in Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticide to aquatic organisms, a comparative study was conducted on the acute toxicity of 39 nonionic, 6 anionic, and 3 cationic surfactants to Daphnia magna. The acute toxicity of three cationic surfactants  1427, 1227 and C8-10 to D. magna belonged to virulent level, and the toxicity of 1427 was the highest, with the EC₅₀ value being 0.97x10^-2 mg·L^-1. The acute toxicity of nonionic surfactants polyoxyethylene ether castor oil EL, Tween, and Span emulsifiers belonged to low level, but the toxicity of alkylphenol polyoxyethylene ether and fatty alcohol polyoxyethylene ether surfactants was relatively high, of which, AEO-7 and AEO-5 displayed high toxicity, with the EC₅₀ value being 0.82 and 0.97 mg·L^-1, respectively. In these surfactants, the more liposolubility, the higher the toxicity was. Most of the anionic surfactants were medium in toxicity, but the acute toxicity of NNO belonged to high toxicity, with the EC₅₀ value being 0.17 mg·L^-1.