Cancer, ranking second among the most commonly encountered diseases worldwide, is exhibiting an increasing incidence over time. Among cancer types, lung cancer, breast cancer, and prostate cancer hold the top three positions. Following these, digestive system cancers are the most frequently observed. The rising cancer-related mortality rates and potential difficulties during treatment exacerbate the fears and concerns of cancer patients. Throughout history, cancer has been attempted to be explained through theories such as lymphatic, humoral, blastoma, trauma, chronic irritation, and parasitic hypotheses. In contemporary times, a wealth of information exists concerning the roles of viruses and bacteria in cancer development. Among bacteria, the sole member acknowledged as a human carcinogen by the International Agency for Research on Cancer (IARC) is Helicobacter pylori. While there is no conclusive evidence regarding Streptococcus bovis's capacity to induce cancer, substantial suspicions surround this matter. This review delves into the relationship between the Streptococcus bovis group of bacteria, which is associated with cancer but not listed by the IARC, and colorectal cancer.