Diabetes Mellitus is a life-long chronic metabolic disease, requiring continuous follow-up and therapy, it reduces the quality of life of patients with acute and chronic complications, mortality, and its economic burden is high. Cancer is the second cause of death, according to the data from World Health Organization. Prostate cancer is one of the most common cancers in the developed world and the second leading cause of male cancer-related death. As with the other cancer types, metastasis is an essential problem that we are facing and it is not clear whether a tumor will metastasize or not in localized state. It has been reported that there are high levels of voltage-gated sodium channels in metastatic prostate cancer cases. Cancer, ever growing with diabetes, is a major health problem. Studies have shown that diabetic patients have higher cancer rates than those of non-diabetics. Metformin is the drug of choice for the treatment of diabetes. Recently, there are studies in the literature regarding metformin reducing the risk of cancer besides its effect on diabetes This review will explain the possible role of the metformin on the three dimensional relationship of prostate cancer, diabetes and ion channels, and provide a significant contribution to clinical trials.