Abstract: This paper describes the results of an investigation on the saline and hypersaline zooplanktons from Jinnan and Yinchuan regions during 1981-1984. 222 samples were collected from 7 localities ranging in salinity from 0.5-286‰. 57 species belonging to 16 families and 39 genera were recorded, among which 32 species belong to Rotifera, 14 species to Branchiopoda and 11 species to Copepoda.According to the rate of occurrence and the average density, the important species are:Brachionus plicatilis, B. angularis, B. capsuliflorus, B. calyciflorus,B. urceus, Notholca acuminata quadrata, Lecane lung, Polyarthra trigle, Colurella adriatica, Pedalia fennica, Moina mongolica, M. rectirostris, Daphnia magna, Bosmina sp., Along rectangula, Artemia salina, Metadiaptomus asiaticus, Arctodiaptomus rectis pinosus, Cyclops vicinus, Apocyclops royi, Mesocyclops lenckarti, Thermocyclops kawamurai and Microcyclops urnoi.Except those for Artemia soling, the upper limits of salinity tolerance of both saline and freshwater zooplanktons in this region are higher than those reported by other authors.Faunal similarities, the salinity tolerance of inland water zooplanktons and relationship between salinity and species diversity were discussed.