There is no specific time for removal of nevus birthmark, in general, the earlier the treatment, the better, relatively speaking, the teenage period is more appropriate age for treatment. Naevus is usually a congenital melanocytic nevus, which can gradually evolve into malignant, so it needs to be regularly reviewed and timely and standardized treatment. Since a few nevi will fade away on their own as they grow older, observation is usually the mainstay. For nevus that grows on the face or other exposed parts of the body, due to the serious impact on aesthetics, it may cause patients to have low self-esteem or depression, etc. However, since the degree of cooperation with the treatment of pre-school children is relatively poor, it is generally more appropriate to carry out the treatment in the teenage years. For nevus that grows too fast or is large in size, it needs to be treated with surgery in time to avoid deterioration. Since the shape and size of nevus vary to some extent, you need to consult a doctor before choosing the appropriate treatment time and treatment method.