Traumatic brain injury (TBI) is an important health issue with high prevalence. The most common type of TBI is mild TBI (MTBI). MTBI is known as a condition with self-limited symptoms; however, it could cause some structural abnormalities of brain and become complicated. Visible structural brain damage could have an important effect on recovery after MTBI, but the outcome is not fully understood. This study investigated the clinical course of MTBI patients with the existence of contusion in computed tomography (CT) imaging. Fifty patients with MTBI and simultaneous brain contusion in CT scan were enrolled according to specific exclusion criteria in 14 month. Patients were followed up for two weeks after their first arrival for neurosurgical interventions, decreased level of consciousness, and other neurological complications. Presence of neurological symptoms increased duration of hospital stay and number of CT scans. Forty-two percent of MTBI patients with contusion did not have any objective neurological signs. Fifty percent returned to the hospital with neurologic symptoms and signs. Leading causes were headache followed by seizure and dizziness. Rehospitalization was increased in the patients with altered level of consciousness. The size of brain contusion increased in two patients without further need for neurosurgical intervention. Contusion alone did not worsen the prognosis of patients in short-term follow-up and did not cause neurosurgical interventions.