Abstract: The acute toxicity of three kinds of stimulating chemical warfare agents, DC, DA and CN, to Brachydanio rerio and Gobiocypris rarus were studied through static and semi-static state processes. To the quality control of testing unstable chemicals, semi-static state is recommended. The results indicated that all of the three chemical warfare agents were highly toxic, in which DC had the highest toxicity, and CN had the toxicity of one order of magnitude lower than DC and DA. The results also showed that Brachydanio rerio and Gobiocypris rarus had the close sensitivity to the three chemical warfare agents.