A randomized, double blind, controlled trial will be conducted in neurosurgery ward, operating room (OR) and intensive care unit (ICU) in Tehran, Iran. After a full review of the inclusion and exclusion criteria and explanation of the risks and benefits of the study, written consent form will be completed. The participants are 60 eligible hospitalized patients that diagnosed with brain tumor and need to craniotomy, aged ≥ 18 years. Intervention patients will be received an intramuscular (IM) single dose of vitamin D (300000 IU). Patients will be evaluated for occurrence of perioperative complications and clinical outcomes immediately after surgery until 1 month later and 1 and 6 months mortality.