The goal of the current investigation is to study the role of vitamin C and acetylsalicylic acid for minimizing the effects of heat stress on blood constituent, growth hormone, HSP 70 and glutathione. Broiler chickens were randomly allocated to four groups: 1st group controlled, the 2nd group subjected to heat stress 40±2 C for 4 hours. / day, the 3rd group was subjected to heat stress and vitamin C (360mg/L) in drinking water and 4th group was subjected to heat stress and acetylsalicylic acid (0.03%) in drinking water. The result showed that exposure to heat stress decline in RBCs count, Hb concentration, PCV% and percentage of lymphocyte, furthermore elevation in of MCV, Heterophils, H/L ratio, and HSP70. Administration of vitamin C caused a significant rise in RBCs count, percentage of lymphocyte and reduces in MCV, MCH value, percentage of Heterophils and H/L ratio compared with the heat stress group. Administrations of acetylsalicylic acid significantly increase in the RBCs, and PCV% and decrease in MCV, MCH, MCHC values, and H/L ratio compare with the heat stress group. The results did not show significant changes between groups in the level of glutathione and growth hormone. It concluded that Vitamin C and acetylsalicylic acid administration as feed additive ameliorating the opposing effect caused by heat stress in broiler chicken; thus, its administration recommended during the heat stress.