Introduction: Controversy exists as to whether post-traumatic stress disorder (PTSD) may occur after traumatic brain injury (TBI). Objective: To describe the clinical presentation and course of a group of patients that developed PTSD following a work-related TBI. Methods: Clinical records of patients with PTSD treated in Hospital del Trabajador between years 1987 and 2001 were examined. Those cases in which a TBI had occurred were selected and compared with those in which a TBI had not preceded the PTSD. Results: 32 patients were identified as suffering PTSD preceded by TBI. All patients had suffered mild TBI; 62.5% of them as a result of a traffic accident. On average, patients were referred for mental health consultation 70 days after TBI had occurred, and 31.2% of them received specialized treatment for less than three months. When discharged 25% were asymptomatic. When compared with 453 patients suffering PTSD, with no history of previous TBI, treated during the same period, those who had suffered TBI presented a greater proportion of physical lesions, more prolonged treatment periods, and a greater proportion of them were still symptomatic when discharged. Discussion: In a group of patients suffering PTSD, history of mild TBI was a factor associated with a worse prognosis