Jatibarang reservoir is one of the reservoir located in Semarang which has a function as a Tourism, a source of clean water and to prevent flooding control to collect water from Kaligarang and Kreo river.. Information on the trophic status of the reservoir is very necessary for the future Management of Jatibarang reservoir. The purpose of this study was to determine the trophic status of waters by nitrate (NO3), phosphate (PO4) , and chlorophyll -a in the Jatibarang reservoir . The results of this study will be expected as a reference management of Jatibarang reservoir.The research was carried out on 15 to 29 March 2016, with the replication of three times with span period of one week.Determining the location of sampling in this study refers to the difference in the activity of Jatibarang reservoir area is further divided into three observation stations . Station I input area (inlet) , the second station in the middle of the reservoir waters and III stations in the output area (Outlet). Each station is done taking two sample points based on the depth of that surface and a depth of 10 meters. The results showed that the trophic status of the reservoir Jatibarang based content from nitrate and phosphate eutrophic and hypertrophic, while the views of chlorophyll-a, including oligotrophic