Abstract: Objective To study the incidence rate,pattern and affective factors of mental disorder due to brain damage. Methods According to CCMD-2-R,388 subjects with traumatic brain damage in the Psychiatric Hospital of Huainan city within last 5 years were assessed by three psychiatrists 6 months to 1 year after brain injury. Results (1) 74.2% of the mental disordered due to brain injury have intellectual impairment,most of them is mild; (2)The intracranial hematoma,brain stem injury,brain injury extent,GCS,complicated mental disorder,and education have great effect on intellectual impairment; (3) There is an intimate relationship between the intellectual impairment and the brain stem injury,intracranial hematoma,GCS,brain injury extent,and unconsciousness time. There is an intimate relationship between the mental symptom and the brain injury extent,contusion and laceration of brain,frontal lobe injury,and intracranial hematoma. There is also an intimate relationship between the personality change and the frontal lobe injury,unfolding brain case treatment,and intracranial hematoma. Conclusion To assess over-all mental disorder should rely on the characteristics of craniocerebral injuries.

Key words: forensic psychiatry, mental disorder, logistic regression, brain damage