Sweat odor may have a physiological cause or may be considered to be related to hyperhidrosis. Physiological odor can be relieved by timely cleaning, and hyperhidrosis can be treated with topical antiperspirants. 1. Physiological reasons: summer weather is hot, through sweating can regulate body temperature. If you don’t wash and change your clothes in time after sweating a lot in your armpits, ammonia can be produced after fermentation and decomposition, which can lead to the odor of sweat in your armpits, which is a normal situation. Through timely cleaning, keep the armpits dry, clean, timely change of clothing, odor can be eliminated. 2. Hyperhidrosis: If the amount of sweating is relatively large, the odor is heavy, the color of the sweat is yellow, but also to understand whether it is related to hyperhidrosis. Patients with hyperhidrosis, the sweat glands in the armpits sweat more, may produce obvious odor. It can be treated with topical antiperspirant, local injection of botulinum toxin, or minimally invasive surgery under the guidance of a doctor. Usually pay attention to personal hygiene, if it is caused by pathological factors, it is recommended to go to the hospital dermatology department, under the guidance of the doctor.