Abstract: The protozoan fauna were investigated in 1990 and 1991 in 28 localities withsalinity ranging from 0.57 to 214‰,in Sanbei districts of northern China. Onehundred and sixty-two samples were collected from these localities,and 13 speciesof Sarcodina and 45 species of Ciliata were found.Protozoa,especially ciliates playan important role in structuring the community of zooplanktons in inland salinewaters. The density and biomass of ciliates is usually higher in hypersaline waters,and ciliates may dominate in the community in some localities.The total numberof species and divcrsity index of protozoan tend to dicline as the salinity increases,and the density and biomass of the organisms increased obviously with the rise ofsalinity. The species composition,distribution of protozoa in inland saline waterswere discussed, as well as the relationship between protozoan fauna and some environmental factors.