Trophic status is an important indicator for a water body. Indicators that can be used include chlorophyll-a as a determinant of whether or not many biota can survive in a body of water. The trophic status of waters can be indicated as water fertility which is closely related to chlorophyll content in phytoplankton. This study aims to determine the trophic status of Banyuajuh waters through the TSI method. This research was conducted from October to November 2022. Water and plankton sampling was carried out using purposive sampling method, with 3 stations and morning and evening time exploration in each week. Water quality parameters include temperature, brightness, pH, DO, light intensity, nitrate and phosphate. Plankton data were identified to determine the species at each station. The results of trophic status research in Banyuajuh waters using the TSI method at station 1 is classified as moderate to severe eutrophic, station 2 is classified as mesotrophic and oligotrophic and at station 3 is classified as moderate eutrophication. Based on the pedeketan used, it indicates that Banyuajuh waters are classified as Oligtrophic to Severe Eutrophication.