This study was conducted to determine the effect of Anacardium occidentale powder as a dietary supplement on growth performance,immune and visceral organ weights of replacement laying pullets.A total of 320-day-old White Leghorn (Hybrid L33) replacement laying pullets were placed for 35 days for trial 1.Birds were assigned to four dietary treatments,with four replicates per treatment and 20 birds per replicate.Two hundred and forty pullets from trial 1 and maintained on their respective treatments were used trial 2 which lasted 3-week (up to 56-days-old).Each treatment was assigned to four replicates of 15 birds according to a completely randomized design.Dietary treatments consisted of a control diet fed without or with 0.5,1.5 and 2.5% supplemental A.occidentale powder.Supplementation of 0.5% of Anacardium occidentale powder increased the BW and the bursa of Fabricius and cecum relative weights at 35 days.However,productive indicators were reduced (P<0.05) with supplementation of 1.5 and 2.5% of A.occidentale powder.Also,variations were observed in the thymus,proventriculus and gizzard relative weights at 56 days.Supplementing A.occidentale powder did not affect the viscera relative weights at 35 days.However,at 56 days the pancreas relative weight was higher in the treatment without powder and the kidney relative weight and intestinal pH (P>0.05) increased with supplementation of 1.5 and 2.5 % of A.occidentale powder.These findings indicate a beneficial effect of dietary supplementation of A.occidentale powder at 0.5% on growth performance,immune and visceral organs in the replacement laying pullets.