There is limited research about head injury. In this existing data study, 2443 admission records of 28367 patients that confer to Loghman Medical Center from 1986-1991 were analyzed. Several factors including age, sex, type and cause of injury, mortality and morbidity were investigated. Overall, the most common age group were 20-40 years, but the most common age group in female patients were 3-6 years. Female to male ratio was 1 to 3. The most common cause of head injury was fallen down and mortality rate was 10.6 percent.