Abstract: The effects of different carotenoid sources on pigmentation of rainbow trout were investigated. The fish (154.35±24.02 g) were fed with diets containing 50 mg kg^-1 astaxanthin, 70 mg kg^-1 canthaxantin and 765 mg kg^-1 oleoresin paprika and compared with a control group for 60 days. Rainbow trout were captured in fresh water in triplicate groups (25 fish tank^-1) at water temperature of 14.74°C. There was no significant difference among experiment groups in the average weights, specific growth rates and feed conversion ratios at the end of the experiment. Feed supplemented with oleoresin paprika, canthaxantin and astaxanthin caused >6 mg kg^-1 carotenoid concentration in the muscle tissues of the fish. The canthaxantin group (10.07 mg kg^-1) developed more of an accumulation than rainbow trout fillets in the other groups. L* a* b* values were determined with a Minolta Chroma Meter. While carotenoid concentration in the trout fillet and red intensity (a*) increased proportionally in the fillet, the brightness (L*) decreased. Tristimulus Chrometer a* values ranged between 0.40 and 9.55; b* values from 11.11-22.14 and L* values from 54.40-45.21. Meanwhile, Chroma (C*ab) and Hue (H_ab^o) angle values, respectively varied 11.13-23.73 and from 87.35-62.43. In the Roche Salmofan^TM card score, the increase in the feed containing oleoresin paprika, canthaxantin and astaxanthin was proportional to the increase in the fillet. While the increase of pigmentation in the fish fillet depended on the increase of carotenoid concentration in the feed, there was a decrease in the carotenoid retention rate. As observed, there is a direct proportional relationship between the color parameters in the muscle and carotenoid concentrations.