Bacteriophages or phages are the most abundant organisms in the biosphere, and they have a unique feature for prokaryotic organisms. Scientists consider phages an appropriate tool for understanding molecular biology, horizontal gene transfer vectors, and stimulants of bacterial evolution, a source of diagnostic and genetic tools and new therapeutic agents. Therefore, research into the biology of phages and their relationship to the host, as we appropriate tools as modulation of the host immune system, is a key to a better understanding of biological systems. Numerous studies confirmed that bacteriophages are a genetic tool with high potential for the treatment of infectious diseases, including bacterial, fungal, and viral infections. Therefore, phages may be used as an appropriate therapeutic target against some viruses, such as COVID-19 infection. In this study, we describe the role of phages in modulating the host immune system, the production of specific antibodies against the COVID-19 virus by the host immune system, and the minimization of damage caused by the COVID-19 virus to the host. Also, the present study expresses our understanding of the prospect of phage therapy as an adjunctive therapy.