Though benthic invertebrates are an important indicator group in determining biological quality in freshwater ecosystems, there are still significant deficiencies in their faunistic composition. Aim of this study to determine the diversity and species composition of benthic macroinvertebrates in Sangı Stream, Izmir (Turkey). With this respect, the six sampling stations were determined through the stream and benthic macroinvertebrates were collected monthly between February 2018 and March 2019. As a result of the analysis, the four benthic macroinvertebrate groups, Crustacea, Oligochaeta, Gastropoda, and Insecta were determined in Sangı Stream. The most dominant taxa were Insecta among all benthic macroinvertebrates. Spatial similarities and differences were also determined by using biodiversity indices and analyses based on species. This study is the first study for determining Sangı Stream benthic fauna, that’s why the all taxa diagnosed in the stream has been recorded for the first time.