To evaluate the effects of butyric acid (BA) levels and wheat form (WF) on the performance of broiler chickens, 320 day-old Ross 308 broiler chicks were randomly distributed among 32 floor pens. A 4 × 2 factorial arrangement with four levels of BA (B 1 : 0 g BA/kg in both starter and grower feed; B 2 : 2.5 g BA/kg in both starter and grower feed; B 3 : 2.5 g BA/kg in starter and 1 g BA/kg in grower feed; and B 4 : 2.5 g BA/kg in starter and 0 g BA/kg in grower feed) and two forms of wheat (whole (WW) vs. ground (GW)) were used. Dietary supplementation with BA had no effect on average weight gain (AWG) or feed conversion ratio (FCR) in the starter, grower/finisher and over whole (0 -42 d) trial periods. However, birds consumed more when the diet was supplemented with butyrate (B 2 ) relative to the control and other experimental diets during 0 -42 d, but this increase was not associated with improved AWG or FCR as compared with that of the control. The BA had no significant effect on relative fat pad, gizzard or breast meat, but increased liver weight. The length of the entire gut was augmented by BA and WW feeding. Feeding WW increased the relative weight of the gizzard and liver, but decreased the relative weight of abdominal fat. Two-way interactions were not significant for any of the carcass traits or organ-size parameters except for breast meat, in which a significant interaction was observed between BA and WF.________________________________________________________________________________