Type 1 Diabetes Mellitus (T1DM) is an autoimmune disease affecting millions of people worldwide that destroys pancreatic beta cells, influencing glucose homeostasis. In T1DM, glucoregulation and carbohydrate oxidation may be altered in different ambient temperatures; however, current literature has yet to explore these mechanisms. This publication examines the effects of 30 minutes of exercise at 65% VO2max in 5ºC, 20ºC and 35ºC in individuals with T1DM. No significant differences were observed for blood glucose across the 3 conditions (p = 0.442), but significance was found for core temperature, heat storage, and sweat rate (p > 0.01). Blood glucose was also shown to vary greatly between individuals among conditions. The mechanisms behind the differences in blood glucose may be due to the lack of significant glucagon production among conditions. These findings suggest that T1DM individuals may exercise submaximally for 30 minutes in different ambient temperatures without significant differences in glucoregulation.