Goal. To analyze the state of open water bodies in the Western region of Ukraine and to identify factors that worsen their quality indicators. Methods. Route agroecological monitoring; methods of chemical and physicochemical analysis using atomic absorption spectrophotometry, flame photometry, and mathematical and statistical analysis. Results. In pond water samples taken in the village Pavlov of the Chervonograd district of the Lviv oblast, an excess of the maximum permissible concentration of nitrate and ammonium nitrogen was found — 11.8–13.2 and 4.6 mg/l, respectively. The content of manganese compounds here exceeded the normative indicators by 5–10 times. On the territory of home ownership in Zakarpattia region (vil. Sokyrnytsia, Khust district) the content of ammonium nitrogen in pond water samples exceeded the norm by 1.8 times, the content of copper by 20 times, and zinc by twice. Analysis of water from a pond located in the vil. Popeliv of the Ivano-Frankivsk district of the Ivano-Frankivsk oblast showed an excess of the norm according to the indicator of dry residue — 2120 mg/l. In water samples taken from the Prut River (vil. Sadzhavka, Nadvirniansk district, Ivano-Frankivsk oblast), the excess of normative indicators only for the iron content was 0.13 mg/l. In the water from the Sluch River (vil. Samchyky, Khmelnytskyi district, Khmelnytskyi oblast), the pH was 8.6, the phosphorus content exceeded the norm by almost two times, and copper by 10 times. In the water from the Dniester River near the vil. Nyzhniv of Ivano-Frankivsk district, Ivano-Frankivsk oblast the content of sulfates and manganese was 156.8 and 0.03 mg/l, respectively. In water samples taken from the Rika River (Khust district, Zakarpatska oblast) the iron content was 11.3 times higher than normal, and manganese was 5 times higher than normal. Conclusions. The results of the monitoring of water bodies in the specified regions proved that both natural and anthropogenic factors affect the water quality of open water bodies. The quality of pond water is largely influenced by anthropogenic factors related to the economic activities of people, and it is they that cause the accumulation of excessive amounts of nitrogen, ammonium, copper, and zinc compounds. The quality of water samples taken from the Prut, Stara, and Rika rivers was mostly determined by natural conditions. Pollution of the Sluch River with phosphorus and copper and the Dniester River with sulfates can be caused by the inflow of sewage with detergents, as well as animal waste, fertilizers, and pesticides from residential areas.