A study was done to evaluate the effect of different levels of tangerine peel powder (TPP) on the growth performance of broiler Cobb 500 chicks from 8-42 days olds. An experiment was randomly designed into 5 dietary treatments and 3 replicates. Each replicate consisted of 30 Cobb 500 broilers at 8 days old. The dietary treatments were as followed as Control: a basal diet only; BTB₁₀₀: the basal diet plus 0,1 % TPP; BTB₁₅₀: the basal diet plus 0,15% TPP; BTB₂₀₀: the basal diet plus 0,2% TPP; and BTB₂₅₀: the basal diet plus 0,25% TPP. The results showed that the infection rate of coccidiosis and culling rate were tended highly on control and BTB₁₀₀ compared to BTB₁₅₀, BTB₂₀₀ and BTB₂₅₀. There were statistically different among treatments on the live weight of birds at 2th, 4th, 5th and 6th weeks of age (P150 and BTB₂₀₀ and lowest on control. No significant differences among treatments were found on daily weight gain, daily feed consumption, and feed consuption ratio (P>0.05). Supplemtation of different levels of tangerine peel powder improved highly 1-14% economical efficence, especially BTB₁₅₀ given 14% higher than control. It is suggested that supplementation of 0.15% tangerine peel powder into the broiler diet should be used for the highest growth and best economic efficiency.