The ability to maintain thermal homeostasis is one of the key criteria for the proper functioning of the organism in response to physical exercise. The aim of this work was to analyze the variations in basal temperatures, temperatures immediately after exercise, and after 15 min of restitution in selected body areas in people with Down syndrome and in the control group. Thirty-six people of both sexes were examined. Group 1 (the control group) comprised 18 healthy people whose average age was 29.89 years (± 1.41) and whose average BMI was 30.21 (± 0.92). Group 2 consisted of 18 people suffering from Down syndrome, with an average age of 27.44 (± 1.58) and an average BMI of 30.49 (± 1.73). It was determined that body surface temperatures varied in both groups, depending on the tested area. Statistically significantly lower temperature values were detected in people with Down syndrome, in all body areas. After the general rehabilitation exercise, a statistically significant decrease in body surface temperatures was observed in both groups, which was greatest in the torso area of people with Down syndrome. After a period of post-exercise restitution, people in the control group exhibited a greater efficiency of thermoregulatory processes, with mean values exceeding basal temperatures.