The factors that cause stuttering clinically are complex, such as closely related to genetic factors, organic brain factors, damaged articulatory organs and psychosocial factors, etc., which are introduced as follows: I. Genetic factors. Through clinical research, it is found that stuttering has obvious family aggregation phenomenon, which may be closely related to multi-gene and multi-level genetic factors. Second, the organic brain factors. In particular, damage to the brain during the perinatal period is one of the main factors leading to stuttering, especially when the cerebral hemispheres, basal ganglia or prefrontal lobes are damaged, the chances of stuttering are significantly higher. Third, damage to the articulatory organs. Some studies suggest that the occurrence of stuttering may be related to the abnormalities of the articulatory organs, such as the respiratory muscles or the organs of the pharynx. Fourth, psychosocial factors. Especially when children grow up in an environment where they stutter, they develop habitual stuttering or stammering because of their strong imitation. In addition, the family education style is too harsh may also lead to stuttering in the process of child development.