Background: Hemostatic abnormalities have been frequently reported in patients with traumatic brain injury. These changes are reported to predict outcome. This study aimed at evaluating the association between coagulopathy detected within the first 12h and outcome in Indian patients with isolated head trauma. Methods: One hundred patients admitted within 12h of head injury were enrolled in the study. Based on the GCS, head injury was classified as mild (GCS13-15), moderate (GCS 9-12) and severe (GCS 3-8). Complete blood count including platelet count, Prothrombin time (PT) and Activated partial thromboplasin time (APTT) were done in all patients. Based on the value of PT (11sec) and APTT (28sec) of laboratory controls, coagulopathy was defined as prolonged PT (>14sec) and/or APTT (>34sec). Patients were followed up till the time of discharge/death. Results: The prevalence of coagulopathy was 39%.Associated thrombocytopenia was observed in 30/ 39 (76.9%) patients while 18 patients had isolated thrombocytopenia. The mortality was 26%.Platelet count was significantly (p<0.001) lower and PT and APTT significantly (p<0.001) higher in non survivors as compared to survivors. The mortality was significantly (p<0.001) higher in patients with thrombocytopenia and coagulopathy as compared to patients in whom these parameters were normal. Conclusion: Hemostatic parameters in patients with isolated head trauma at admission may be used to identify patients with a poor outcome.