Đetinja river waters are used for water supply of settlements and industries in the basin. The length of the river is 75.25 km. Water quality along the flow changes. Results of biological and chemical analysis indicate the degradation of river ecosystems through the city of Užice and downstream. The problem of pollution and protection of surface water must be analyzed in detail because this is one of the most valuable natural resources in area. The paper describes the state of water quality of Đetinja, register the largest polluters and suggest measures for its protection.