**Abstract**

The immune system is influenced by vitamin B complex: B1, B2, B3, B5, B6, B7, B9 and B12. The B complex insufficiency can cause significant impairment in cellular and immune function and trigger an inflammatory response. There is currently no certified SARS-CoV-2 treatment or a credible vaccine, but strengthening the immune system with B vitamins could go a long way in preventing and treating COVID-19 patients. Thus, a complete and nutritious diet must be followed before approved drugs and potential good vaccine research results are available to boost the normal functioning of the immune system. In order to activate adaptive and inborn immune responses, reduce cytokine levels such as proinflammatory cytokines, decrease oxidative stress, preserve endothelial homogeneity, improving pulmonary function, prevents hypercoagulable conditions and shortening the length of hospital stay; B-Complex vitamins play a significant role. Thus, the role of B complex in patients with COVID-19 needs to be evaluated and additional nondrug B vitamins can be used in existing treatments.

**Keywords:** vitamins, immunity, COVID-19, inflammation, cytokines, anti-oxidant
