Cancer is one of the leading causes of death worldwide; despite the considerable progress made by researchers in the diversity of cancer treatment methods, the mortality rate from malignant tumors is still alarmingly high. So, discouraging cancer growth and reducing its spread is one of modern medicine’s major challenges. Viral therapy is one of the most promising experimental therapies for cancer which detect viruses that can kill cancer cells. The detected viruses can be used to treat malignant tumors, which is done through the replication of the virus inside malignant tumor cells. The clinical use of oncolytic viruses has been shown to have positive results in the treatment of some types of cancers. Virotherapy is different from chemotherapy. The goal of virotherapy, not unlike that of radiation therapy and chemotherapy, is to destroy cancer cells, but virotherapy has several distinct advantages: Virotherapy destroys tumor cells selectively without affecting the healthy cells of the body. Directly infects tumor cells and their antitumor efficiency. Allows healthy cells to remain intact by targeting those cells with pathogens. Preserves and stimulates the immune system, signaling a viral antitumor response to destroy remaining cancerous cells.