Effect of phytase produced by thermo-protective coating technology (coated phytase) on performance and nutrient utilization of broiler chicks fed a corn-soybean meal-based pelleted diet was investigated. A total of 144-one-day-old male broiler (Ross) chicks were divided in 24 groups and fed 4 diets (6 groups per diet) for 21 days. The diets included a mash or pelleted basal diet without or with the coated phytase at 500 FTU/kg in a 2 X 2 factorial arrangement. Calcium and non-phytate P values in the basal diet were 22 and 51% lower compared with NRC (1994) recommended values, respectively. All the diets contained titanium oxide as an indigestible marker. There was no interaction (P > 0.05) between diet form and phytase on any of response criteria measured in this study except body weight gain and feed intake such that phytase supplementation improved (P < 0.05) these 2 response criteria, but improvements were greater for pelleted diet than mash diet. Phytase supplementation increased (P < 0.05) tibia ash and ileal P digestibility, by 10.5 and 38.1%, respectively. Phytase supplementation did not, however, affect (P > 0.05) the ileal digestibilities of Ca, crude protein and amino acids. In conclusion, coated phytase supplementation to corn-soybean meal-based diet for broilers resulted in improved growth performance, bone mineralization and P digestibility regardless of diet type (mash versus pellet). These findings suggest that the efficacy of the coated phytase used in the current study was not influenced by the pelleting process.