Heat stress (HS) is one of the most significant stressors in the broiler industry in hot regions. In order to provide complete information on the impact of turmeric powder (TP) on hamartiology, biochemistry and thyroid hormones of broilers under thermoneutral conditions (TN) (22 ± 4 °C) and heat stress (HS) (34 ± 2° C), the present research was carried out. A 60 of one-day-old (Cobb) broiler chicks, 15 birds in each replicate either control (basal diet) or 0.5% turmeric. Chronic HS at 42 d of age resulted in significant decrease in HGB, PCV, RBCs, total protein, Albumin, serum T3 and T4, whereas increased H/L, triglycerides, cholesterol, LDL-cholesterol, uric acid, AST, ALT, ALP, TBIL, DBIL and creatinine significantly. Supplementation of 0.5% TP significantly increased HGB, PCV, total protein, while significant decrease in AST, ALT, ALP, uric acid, total cholesterol and triglycerides. Results indicated that groups receiving turmeric have improved lipid profile.