Abstract: This study was designed to evaluate the effect of various levels of Full-Fat Safflower seed (FFSS) on performance in broiler chickens. Diets containing various levels of FFSS (0, 5, 10, 15 and 20%) were given to broilers from 21-42 day of age. About 350,21 day old broiler chickens were weighted and distributed randomly to 5 treatments with 5 replicates (14 chicks in each replicate) in each treatment. Blood parameters and carcass traits were determined at 42 days of age. FFSS levels did not significantly affect weight gain, feed intake and Feed Conversion Ratio (FCR). Breast yield, thighs, gastrointestinal tract, liver and gizzard weight percentages were not affected by dietary treatments and abdominal fat pad percentage did not significantly decrease. Triglyceride and total serum protein concentrations were not affected by FFSS levels but cholesterol concentration was significantly decreased (p<0.05). The results of the current study indicated that FFSS could be used up to 20% of broiler diets without any adverse effects on performance or other parameters of chickens.