A total of 459 broiler chicks were studied from 1 to 32 days of age to evaluate the effect of phytase diet supplementation on their growth performance, nutrient digestibility, and meat quality. Chicks were randomly divided into 3 treatments (9 replicates/treatment, 17 chicks/replicate). This was a 32 day experiment that included 2 phases: phase 1, grower (0 to 17 day); and phase 2, finisher (17 to 32 day). Dietary treatments were: T1, control basal diet (CON); T2, CON + 0.01% phytase (300 IU); and, T3, CON + 0.01% phytase (500 IU). Results showed that supplementation of the basal diet with phytase increased pH value of meat. During the period between day 7 and 17 of the study, T2 and T3 groups had higher body weight gain (BWG) than T1 group. After phase 2 and the use of finisher feed, T3 group had significantly improved BWG and feed intake (FI). During the whole experiment, T3 resulted in higher BWG and FI than other treatments. But feed conversion ratio was not affected by phytase supplementation throughout the experiment. Both T2 and T3 groups had significantly higher apparent total tract digestibility of dry matter when compared with T1. However, no differences were observed for Nitrogen, Ca, and P during the experiment. In conclusion, supplementation of phytase increased BW, FI, and apparent total tract digestibility (ATTD) of dry matter (DM). However, there was no significant influence in feed conversion ratio (FCR), relative organ weight and breast muscle quality.