The habit of nail biting, known medically as nail biting, is the act of consciously or unconsciously chewing or destroying the cuticle and surrounding soft tissues of the nail. Nail biting is common in children and adolescents, declines after age 18, and may also persist in some adults. Changing nail biting usually takes a long time and can be done in the following seven ways: 1. Publicity and education: nail biting is a bad habit, long-term nail biting is not good for teeth and oral hygiene, and may also cause rough nail beds and nail fungus, etc. Publicity and education can be given to patients to make them aware that nail biting is a bad behavior; 2. Analytical guidance: analyze the causes of nail biting and give comprehensive, correct and reasonable guidance, family members can spend more time observing the patient’s performance before and after the appearance of nail biting behavior, such as whether they have been alone in a lack of stimulation for too long, to intervene from the cause; 3, distraction: nail biting has often developed into a subconscious behavior, to distract the patient’s attention, such as the patient bites his nails while watching TV, you can let the patient grab an object in his hand, if the patient wants to bite his nails, you need to first put down the object and bring the behavior to the conscious level, it is possible to stop in time; 4. Cut nails diligently: ensure that the length of the nail is in the range that is not easily bitten off, but do not cut it too short to avoid damage to the fingertips; 5. Interrupt the mouth-hand contact: you can choose to use some natural or artificially manufactured edible nail polish, or try to wear light gloves or finger covers to temporarily interrupt the mouth-hand contact; 6. Positive reinforcement without punishment: do not control the patient by scolding or punishing, but rather maintain a gentle and calm mind. Many nail biting behaviors are accompanied by psychological tension, which cannot be well controlled by themselves, and admonishing will only increase anxiety and make the bad habit worse. Calmly point out the patient’s bad behavior, offer possible options to try, and give clear praise and encouragement when short-term results are achieved; 7. Psychological counseling: Excessive frequent or severe nail biting may be associated with a deeper psychological disorder that requires medical intervention or medication. Sometimes symptoms such as attention deficit, hyperactivity disorder, separation anxiety, and tics can be observed at the same time and require timely intervention.