Undertaken studies on diversity and prevalence of yeast-like fungi aimed at presenting the role of a hydrophyte treatment plant in cleaning municipal wastewater from potentially pathogenic fungi. One hundred and six isolates of fungi were obtained. The highest diversity of species was found in the sedimentation tank and in I and II reed beds. The dominating species were: Trichosporon beigelii, Candida albicans, Candida glabrata, Candida dubliniensis, Candida krusei, Candida utilis and Candida lipolytica – isolated also from hospitalized patients. The number of fungal cells decreased progressively from uncountable in the sedimentation tank to 2,060 cfu/dm³ in the polishing pond. Reduction of the number and changes in species composition of yeasts like fungi take place in the hydrophyte treatment plants.