AIM: To evaluate clinical status of patients with chronic subdural hematoma (CSDH) on hospital admission and to predict their outcome after the neurosurgery treatment using Karnofsky index scale (KI). METHODS: Clinical and surgery data of patients with CSDH were collected prospectively. Fifty 50 adults aged over 41 with CSDH diagnosed and hospitalized between November 2010 and April 2012 were investigated. In the analyzed sample there were more CSDHs in males than in females (1.5:1). The diagnosis of CSDH on hospital admission in patients was confirmed by non-contrast computed tomography (CT). Forty-three patients had undergone surgery with Burr-hole drainage and craniotomy, while seven patients were treated conservatively. The KI was used for evaluation of the patient's clinical state before neurosurgery treatment and the quality of survival in all patients, six months after hospital discharge. RESULTS: A statistically significant difference was found between the KI values in patients with CSDHs on hospital admission and KI after the surgical treatment. Six months after, out of 43 patients who underwent surgery in 24 (55.8%) patients KI was between 80-100%, in nine (20.9%) patients KI was between 50-70% and in 10 (23.2%) patients KI was 0-40%. CONCLUSION: Although the elderly with CSDHs are vulnerable because of their age, associated diseases and risk of recurrence of CSDH, their outcome assessed by KI after surgical treatment was good. The Glasgow Coma Scale (GCS) is used for rapid assessment of the state of consciousness in patients on admission and monitoring of the changes in their condition. KI scale could be used as a complementary assessment tool for the general condition of patients with chronic subdural hematoma. This study highlighted that the KI scale had a predictive value for patient's outcome with chronic subdural hematoma.