The main purpose of this study was to measure of nutrients level from the confluence area of Siret and Prut rivers with the Danube and in a few representative points, situated in upstream and downstream of the cities Braila, Galați and Reni. Was determined 8 representative indicators, respectively: ammonium nitrogen (N-NH4), nitrite nitrogen (N-NO2), nitrate nitrogen (N-NO3), total nitrogen, orthophosphate phosphorus (P-PO4), total phosphorus and chlorophyll „a”, from 5 sampling points located along the Danube, 2 sampling points on the Siret river (1 sampling point upstream river and 1 point in the discharge area of river in Danube) and 1 sampling point situated in the confluence area of the river Prut with the Danube. The results obtained showed an increase of concentrations with 1.12 mg / L for the total nitrogen, between the monitoring points situated in Brăila upstream and Brăila downstream. The values of phosphorus concentrations from orthophosphates (P-PO4), showed an increase downstream of Galați city. In discharge area of the Siret river in the Danube, was identified the highest values for total phosphorus and ammonium nitrogen (N-NH4). However, quality indicators determined, did not present exceedances of the maximum admissible concentrations imposed by the Romanian legislation. Acknowledgement: We acknowledge the funding from ENI project eMS code BSB27 MONITOX (2018-2021), Joint Operational Programme Black Sea Basin 2014-2020.