The effects of different levels of dietary fat on calcium (Ca) and phosphorus (P) absorption growth performance, Ca and P percentages of plasma, bone and ash were studied in broiler chickens (Ross 308) during 56-days rearing period. A total of 360 one-day-old chicks randomly assigned to eight experimental groups, three replicates (10 birds per each) of both sex. The experimental groups with a 4 × 2 factorial design received either four levels of fat (0, 2, 4 & 6% of diet) or two levels of Ca (1 or 2% of diet). The results showed that administration of different fat levels to broiler diets were significantly improved growth performance (P< 0.01). Also Ca and P concentration of plasma, bone and ash were increased (P< 0.01) with the exception of bone ash (BA) (P> 0.01). The interaction between fat and Ca for bone P and plasma Ca and P was detected (P< 0.01). There were no interactions detected for feed intake, feed efficiency, carcass weight, ash P and bone Ca and P (P> 0.05). From these results, it was concluded that a combination of 2% animal fat and 1 or 2% Ca provides more suitable performance in broiler chickens and this combination could improve Ca and P absorption; however, higher levels of supplemented fat may decrease absorption rate. [ABSTRACT FROM AUTHOR]