Although protected, special nature reserves are not isolated from anthropogenic influences entering from outside their borders. Water quality is particularly endangered at three special nature reserves in Vojvodina, i.e. Ludaško jezero (Ludas Lake), Carska bara (Imperial Pond) and Obedska bara (Obed Pond). The special nature reserve Obed Pond and Ludas Lake are polluted by agricultural runoff and untreated wastewater resulting in serious eutrophic processes, and the SNR Imperial Pond is potentially influenced from nearby fish pond and agriculture. The monitoring conducted in summer and in autumn in 2016, at the three mentioned special nature reserves, included water sampling on several locations within each protected area. The analyses included basic water quality parameters, microbiological analyses, as well as water mineralization. Both, water quality and microbiological results, have proven the presence of eutrophic processes at all analyzed protected areas, but the worst conditions were detected in the North and Middle of the Ludas Lake. Considering the other two investigated protected areas, results are a bit better indicating moderate eutrophic conditions.