The invention discloses a meat chicken nutrition adjusting and controlling method under a heat stress condition, belonging to the technical field of biology, wherein the heat stress condition is that the temperature T is higher than or equal to 22 DEG C. Aiming at stress reaction of meat chickens in different high-temperature ranges, different nutrient substances and heat stress-resistant pharmaceutical compositions having heat stress-resistant effects are provided in the different high-temperature ranges, namely, influence of heat stress to the meat chickens is eliminated or reduced by comprehensively utilizing the adjusting and controlling effects of the nutrient substances; therefore, injured tissues, such as stomachs and intestines, are prevented from being injured; or, rapid recovery of the injured tissues, such as stomachs and intestines, is promoted; and the heat stress-resistant function is increased. The meat chicken nutrition adjusting and controlling method under the heat stress condition based on physical discomfort indexes, disclosed by the invention, is capable of obviously relieving adverse effects due to high temperature, increasing the productive performances, the heat-resistant capability and the weight uniformity of the meat chickens and reducing the death and culling rate in marketing.