The aim of this study was to evaluate the effects of wavelength of light and duration of illumination on the growth characteristics of broiler chickens of the Ross 308 line. at the Ministry of Agriculture - Department of Agricultural Research - Livestock Research Division - Poultry Research Station. three hundred one day of age male broiler chicks were used, divided randomly into 5 groups with replicates (20 birds per replicate). Treatments consisted in a: negative control treatment (C-); Long illumination, 23 hours of light (white): 1 hour of dark; Positive control treatment (C+);short illumination, 20 hours of light (white) with 4 hours of darkness; other treatments GL, RL, and BL, 20 hours of light with 4 hours of darkness (green, red, and blue, respectively). body weight, carcass weight, percentage of dressing (with and without internal organs), relative weights of primary and secondary carcass parts, abdominal fat and relative weights of certain organs of the digestive and immune systems were not found to differ significantly between treatments.