This study was undertaken to determine the microbiological qualities of rainbow trout skin, feed and water samples obtained from 3 trout farms in Ankara district. A total of 126 samples as 84 skin. 21 feed and 21 water samples were used. Aerob mesophyl viable count. Enterobacteriaceae, Coiiform, Pseudomonas spp. and yeastmould counts were determined with drop plate technique. As a result of this study, microorganism count levels in the skin samples obtained from A, B and C farms were determined as follows: aerob mesophyl viable count levels were 1.4x10* cfu/cm2 , 2.9x10* cfu/cm2 and 5.5x10* cfu/cnr: Eiuerobarteriaceae levels were 2.6xl03 cfu/cnr, 2.6x10s cfu/cnr and 5.2x10" cfu/cm2 : Coiiform count levels were 1.5x10' cfu/cnr, 1.3x10' cfu/cm3 and 5.0xI04 cfu/cm2 ; yeast-mould levels were l.lxIO5 cfu/cm1 , 2.1x10s cfu/cm3 and 9.7x10'' cfu/cm3 ; Pseudomonas spp. counts were 1.0x10 J cfu/cm2 , 2.1x10s cfu/cm3 and 3.7xl03 cfu/cm2 . respectively. Mean counts were determined in water samples obtained from A. B and C farms as follows: aerob mesophyl viable count levels were 1,2x10s cfu/ml, 3.6x10* cfu/ml and 2.3x10 4 cfu/ml: Enterobacteriaceae levels were 2.0x10" cfu/ml, 7.2x10' cfu/ml and 2.9x10'cfu/ml; Coiiform count levels were l.lxIO2 cfu/ml. 2.9x10' cfu/ml and<2.0x!0; cfu/ml; yeast-mould levels were 7.8xl03 cfu/ml, 2.2x1ü"1 cfu/ml and 1.4x10' cfu/ml: Pseudomonas spp. counts were 7.5xl04 cfu/ml. 3.9x10s cfu/mland 1.2x10' cfu/ml, respectively. Mean counts were determined in feed samples obtained from A, B and C farms as follows: aerob mesophyl viable count levels were 1.3x10 5 cfu/g. 3.2x10 5 cfu/gand 9.7x10s cfu/g: yeast-mould levels as 9.1xI0? cfu/g, 1.4x10 4 cfu/g and 2.6xl05 cfu/g, respectively. As a conclusion, rainbow trout samples had poor hygienic qualities and especially consuming these trout samples could cause a potential risk for public health as a result of harbouring to pathogenic microorganisms such as E.coli. Thus, those farms must be controlled periodically.