Siberian sturgeon fry coming from three different ponds has been examined. 1. "Dgał" - fish culture conerete-terrestrial pond beloning to D.O.Z. Dgał Inland Fisheries Institute in Olsztyn supplied with fresh water from Great Dgał Lake; 2. "Grzmieca" - fish culture pond terrestrial, natural belonging to fishing farm Grzmieca near Brodnica; 3. "Konin" - fish culture pond near Konin supplied with water utilized by near heat and power generating plant. Total of 80 sturgeons fry with parameters: length 17.5 cm - 38.5 cm, weight 21 g - 134 g, age 0+1+ has been examined. The examinated group of sturgenos had metacercariae Diplostomum sp. in their lenses. Prevalence of infection of sturgeon with metacercariae Diplostomum sp. was high in all this three ponds. Intensity of infection was also high in ponds "Dgal" and "Grzmieca", but low in "Konin". In ponds "Dgal" and "Konin" we have obtained high positive correlation ("Dgal" - r = 0,606, p < 0,05; "Konin" - r = 0,743, p < or = 0,01) between number of metacercariae in sturgeon and temperature of water. Our study confirmed observations other authors susceptibility sturgeon fry on the Diplostomum sp. invasion.