Background: Bacterial pneumonia of is common cause of pediatric mortality and hospital admission. Different risk factors for pneumonia are there. One possible risk factor is vitamin D deficiency .Objective: We determined 25 OH-vitamin D in bacterial pneumonia.to evaluate whether its level has relation to pathogenesis and management of the disease Design: case-control study Methods: 25 OH-vitamin D was determined by competitive enzyme immunoassay (EIA) commercially available kit in 36 cases with pneumonia CRP was determined by ELIZA "high sensitive CRP" .ESR done by Wintrobe method The results were analyzed and compared with 16 controls using SPSS 20 Results: Vitamin D level in pneumonia cases was significantly lower in patients compared to controls and showed negative correlation with C-reactive protein and weak negative correlation ESR. Vitamin D did not show any relation to age, sex, weight or other clinical symptoms as dyspnea and fever Also did not show any relation to RBCs, Hb, or WBCs .Conclusion: We conclude that level of 25 OH-vitamin D is low in children with bacterial pneumonia and correlates negatively with CRP with possible relation to disease severity.