Causes of stuttering include psychological and mental factors, environmental factors, personality factors, and developmental delays. 1. Psychological and mental factors. Stuttering can occur if the patient is under too much psychological pressure, anxiety, nervousness and so on. For example, parents have too high expectations of their children, which makes the children’s psychological pressure too high, and stuttering can occur. 2. Environmental factors. If there are people who stutter around the patient or in the family, but unconsciously imitate them in normal life, it can also cause stuttering. 3. Character factors. If a person is too introverted, impatient, and speaks too fast, he or she may stutter and stammer incoherently. 4. Developmental delay. Stuttering can also be caused by a variety of reasons that delay the development of the patient’s nervous system. When stuttering occurs, symptoms can be improved through psychological care, concern for the child, etc. It is recommended to intervene under the guidance of a doctor’s interview.