The small mysid crustacean Neomysis awatschensis was collected in the west coast of Jiaozhou Bay, Qingdao, China in 1992 and acclimated and cultured in laboratory conditions since then. Standard acute toxicity tests using 4-6 d juvenile mysids of this species were conducted and the results were compared with Mysidopsis bahia, a standard toxicity test organism used in the US in terms of their sensitivities to reference toxins, as well as their taxonomy, morphology and geographic distributions. Because of its wide distribution along the Chinese coast, similar sensitivity to pollutants as M. bahia, short life history, small size and the ease of handling, this study intended to use N.awatschensis as one of the standard marine organisms for toxicity testing in China. The species were applied to acute toxicity evaluations of drilling fluid and its additives, organotin TPT and toxic algae, and to chronic ( life cycle) toxicity assays of organotin TPT and a toxic dinofalgellate Alexandrium tamarense, respectively. Using N. awatschensis as a standard toxicity testing organism in marine pollution assessment in China is suggested.