First, the ambient temperature is too high and too hot. In summer, the home is not well ventilated, the dog's hair is thick, and the closed and stuffy car is a common cause of heat stroke. Second, the hot weather and strong direct sunlight. Dogs that are exposed to high temperatures for long periods of time or exposed to direct sunlight for long periods of time can cause heat stroke. Finally, in summer, dogs perform high-intensity activities or training, resulting in heatstroke due to lack of water and heat accumulation in the body. In addition, prolonged indwelling of the tracheal intubation during anesthesia, cardiovascular and genitourinary diseases, and obese bodies can also prevent heat from escaping and cause heat stroke.