Abstract: The development of malignant tumors is influenced by multiple factors, including genetics, environment, lifestyle, and pathogen infection. Viral infection plays a significant role in tumor development and progression. This article integrates the common pathways of seven oncogenic viruses (HPV, EBV, HBV, HCV, KSHV, HTLV-1, and HIV) based on the theory of cancer toxin pathomechanism. The findings reveal that cancer toxin formation is influenced by both internal factors (healthy qi deficiency, viscus dysfunction, and qi, blood, and body fluid stagnation) and external factors (viral infection, environmental factors, and the six exogenous pathogens), driving tumor development, metastasis, and recurrence. Viral infection not only provides the material foundation for cancer toxin but also accelerates its maturation and spread through chronic inflammation and immune imbalance, forming a complex pathogenesis of "viral toxicity-endogenous cancer toxin", which translates into a three-stage strategy of "prevention, treatment, and post-recovery prevention". This article systematically discusses the pathogenesis of major cancer toxins and their associated tumors. Integrating the cancer toxin theory, the article explores preventive and therapeutic strategies for virus-associated malignancies, providing a theoretical basis and practical reference for the integrated prevention and treatment of tumors using traditional Chinese and Western medicine.