Abstract: In order to determine the blood biochemical indexes of Jintang black goats at different ages, genders and at higher and lower temperature humidity index（THI）, and to provide basis for environmental regulation and feeding management, The dry and wet bulb temperatures in the goat house were measured at fixed points and the THI was calculated in the experiment. 48 Jintang black goats were randomly selected for the experiment, and there were 16 goats in each age groups of 1, 2 and 3 years old, with half male and half female（the female goats were nonpregnant）. Under the conditions of THI of 85.96, 83.44 and 69.04, blood was collected from the jugular vein, and 14 indexes such as serum adrenaline（EPI）, growth hormone（GH）, thyroxine（T₄）, alanine aminotransferase（ALT）, γ-glutamyl transferase（γ-GT）, alkaline phosphatase（ALP）, aspartate aminotransferase（AST）, cholinesterase（CHE）, total bilirubin（T-Bil）, direct bilirubin（D-Bil）, total protein（TP）, albumin（ALB）, total bile acid（TBA） and glucose（Glu） were measured according to the age, sex and different THI and serum biochemical indexes were compared and analyzed. The results showed that with the increase of age, the ALT activigy and the concentration of TP,ALB and TBA increased（P＜0.05 or P＜0.01）, while the ALP activity and the concentration of Glu decreased（P＜0.01）. The GH concentration of female goats was significantly higher than that of male goats（P＜0.05）, the concentrations of T₄ and ALP activity were significantly higher than that of male goats（P＜0.01）, and the γ-GT activity was significantly lower than that of male goats（P＜0.01）. Under higher THI condition, the concentrations of EPI, T₄ and GH were higher, and the concentrations at THI 83.44 and 85.96 were significantly higher than those at THI 69.04（P＜0.01）. When THI was 69.04 and 85.96, the concentrations of ALB and γ-GT activity were higher in the former than in the latter, while the concentrations of T-BIL, D-BIL and TBA were higher in the latter. This showed that ALT, ALP activity and TP, ALB, TBA, and Glu concentrations were related to age. The ALP, γ-GT activity and GH, T₄ concentration were related to gender. Under higher THI conditions, EPI and T₄ levels revealed that Jintang black goats were under heat stress, while GH levels were high, and major liver function indexes such as ALT and AST were decreased.