Background: In the pandemic of COVID-19 because an adequate immune response is crucial for overcoming this viral infection, it is important to identify the existing and known substances that strengthen immune system activity. On the other hand, India being a tropical country is blessed with sunlight in almost all of its territory and so it would be more interesting to have an estimate of vitamin D levels representative of the Indian population who suffered from COVID-19 infection. Aim: To study the levels of vitamin D in patients with COVID-19 infection. Material and Methods: This study is a cross-sectional study conducted for estimating the prevalence of vitamin D deficiency in patients diagnosed with COVID-19 infection. The present study was conducted at tertiary care COVID-19 hospital at Indian Institute of Medical Science and Research, Jalna, Maharashtra in collaboration with Hedgewar Multispeciality Hospital, Aurangabad, Maharashtra. Result: Among the 141 study subjects 86 were vitamin D insufficient, 38 were vitamin D deficient while the remaining 14 subjects were having normal vitamin D levels. When the prevalence rate was estimated from this data the prevalence of vitamin D insufficiency was reported to be 60.99% whereas the prevalence of vitamin D deficiency was found to be 29.07% in the COVID-19 population of this study. Conclusion: Vitamin D deficiency and insufficiency were prevalent in COVID-19 patients and so vitamin D supplementation may help in the prognosis of COVID-19 disease.