The presence of nevus-like black spots on one side of the tongue is recommended to hang up with the stomatology department for consultation and treatment. It is generally considered that it may be caused by local friction, inflammation, hyperpigmentation and other factors. 1. Localized friction: localized friction and injury on one side of the tongue may lead to localized bleeding, and the surface looks like a mole. If the black spot is not enlarged, this condition usually does not need treatment. When the black spot is enlarged or painful, it is recommended to go to the stomatology department for treatment in time. 2. Inflammation: Inflammation can lead to localized nevus-like changes, you can follow the doctor’s instructions to use compound chlorhexidine gargle, etc. Dietary advice is to eat a light diet, drink more hot water, and promote the body’s metabolism. If there is no improvement, hospital treatment is recommended. 3. Hyperpigmentation: If it is simple hyperpigmentation, there is no need to treat it, but if it is a pigmented tumor, it is recommended to go to the hospital for surgery in time to prevent cancer. If there is any abnormality, please consult the doctor in time and treat it positively, do not use medicine privately, so as to avoid danger and delay the condition.