The present paper deals with the Mysidacea fauna of the North China waters ——the wes tern part of Yellow Sea and the Bohai Sea. The materials studied were collected by the Institute of Oceanology and the Institute of Zoology, Academia Sinica, from shallow waters off the North China coasts during the past thirty years. Through the present study the authors found that the mysid fauna of the northern part of China seas is comparatively poor in species, but several species of this group, e. g. Neomysis awatschensis, N. japonicus, Acanthomysis longirostris, etc., are very abundantly distributed in shallow seas, particularly in coastal waters of low salinity and estuaries of rivers, and are of economic importance in local fisheries. They are utilized and sold in fish market freshly or as shrimp paste as nutrient food for human consumption .as well as for cultivated shrimps. A total of 16 species belonging to 3 subfamilies and 8 genera of the Family Mysidae were identified, of which 2 are described as new, namely Pseudomma brevicaudum Shen et Liu sp. nov. and Acanthomysis sheni Wang et Liu, sp. nov. The latter species is named in honour of the founder of Chinese carcinology, the late Professor C. J. Shen. The type materials of the new species are deposited in the Institute of Oceanology, Academia Sinica, Qingdao.