In this study, we isolated Candidasp. for the first time from fry of rainbow trout (Oncorhynchus mykiss) in Turkey. Candida species caused disease in fry (average 0.2 g) whichwas observed at 10°C water temperature in February 2016. Due to yeastaccumulation on gills, whitish areas was seen and fusion of secondary lamellain gills were observed under microscope. The microbiological samples of kidney,spleen and gills were streaked onto trypticase soy agar (TSA) and tryptoneyeast extract salts (TYES) agar platesand incubated at 22°C in TSA and 18°C in TYES agar for 48 h. Thirteen isolateswere obtained and Gram staining was performed. The all of the isolates were determined as yeast cellbased on cellular morphology by using light microscopy. The identification was performed by ITS (Internal transcribed spacer) regionsequence analysis and sequence data demonstrated that representative isolateD11 belonged to genus Candida. Theyeast infection might have seen in early development stages (larvae and fry)due to the intensive antibiotic use against rainbow trout fry syndrome (RTFS)disease.