Zooplankton is an important group in aquatic ecosystems. They act as biological indicators as they are influenced by both biotic and abiotic factors reflecting the change in water quality, eutrophication and pollution over time because they respond quickly to changes in the water body. Zooplankton of some torrent streams in Taif governorate, KSA were studied. Thirty-nine zooplankton species were recorded, in the studied water bodies during the present work. They were belonging to five zooplankton groups, Rotifera (20 species), Cladocera (5 species), Copepoda (3 species), Protozoa (6 species) and meroplankton (5 species). Rotifera was the dominant group and highly represented in site I, while Cladocera was the lowest according to their population densities. On the other side, site IV showed the lowest Rotifer density and the highest cladoceran density. This is attributed to the pollution caused by sewage discharge from the nearby treatment plant.