Background: COVID-19 is the pandemic disease declared by World Health Organization (WHO) on 11th March 2020. Growing body of evidence suggests that a vitamin D deficiency could be linked with developing a more severe case of COVID-19. The possible correlation between Vitamin D insufficiency and worse outcome has been postulated to be associated with metabolic, procoagulant and inflammatory events and is not independently related to COVID-19. Objectives: To evaluate the vitamin D status in patients with COVID-19 and prediction of outcome. Method: This prospective study was conducted at Armed Forces Institute of Pathology (AFIP) and Combined Military Hospital, Dhaka Cantonment from April 2020 to August 2020. One hundred COVID-19 positive cases admitted in CMH, Dhaka were enrolled. Detail socio-demographic data were collected from the informant and recorded in structured questionnaire. Clinical examination and relevant investigations were done. All collected data were analysed under SPSS-21 version. Result: Out of 100 cases in this study, maximum patients (43.0%) were in age group 41- 50 years, mean age of the patient was 42.35 ± 11.7 years. Male to female ratio was 3.54:1, 78% were male and 22% were female. Vitamin D deficiency was found in 15.0% cases and vitamin D insufficiency was found in 28.0% cases. On evaluation of outcome, 65.0%patients were recovered completely, complications were developed among 27.0% patients (17.0% cases required noninvasive ventilation and 10% cases required invasive ventilation) and 8.0% were died. Among the expired 8 patients, 7(87.5%) had deficient and 1(12.5%) had insufficient vitamin D. Among the recovered patients, maximum 54(83.0%)had normal vitamin D level. In this study high prevalence of hypovitaminosis D was found among patients not recovered and expired. Conclusion: Present study concluded that vitamin D can predict the outcome of COVID 19 patients.