Objective To Screen suitable development stage of Mugilogobius chulae for acute toxicity test. Methods The prelarva, middle larva, postlarva, juvenile,young, adult of M.chulae were exposed to five concentrations of water-based drilling fluid and a control group and compare the acute toxicity of drilling fluid to M. chulae in different development stages. Results The 48h median lethal concentration(LC50) of the drilling fluid to M. chulae prelarva was 157 mg/L and to the middle larva was more than 500 mg/L. The 96h LC50 to the middle larva was 79 mg/L and to the postlarva was 625 mg/L.The 96h LC50 of the drilling fluid to juvenile, young and adult obviously exceeded 500 mg/L. That of the drilling fluid to Artemia nauplius was 105 mg/L.The sensitivity sequence of M.chulae in different development stages to drilling fluid was prelarva﹥middle larva﹥postlarva﹥juvenile, young and adult.Concolusion Prelarva of Mugilogobius chulae is suitable as laboratory organism for acute toxicity evaluation of marine pollutants