This review provides an in-depth examination of CD8+ T cell-based cancer immunotherapy, highlighting the critical role of CD8+ T cells in anti-tumor immunity and the mechanisms of tumor immune escape. CD8+ T cells, crucial for recognizing and eliminating tumor cells, face challenges from tumor-induced immune evasion strategies. The review covers the life cycle of CD8+ T cells, from their generation and activation to their function and fate. It discusses various mechanisms by which tumors evade CD8+ T cell recognition, including downregulation of immunogenicity, secretion of immunosuppressive factors, expression of immunosuppressive coreceptors, and the formation of an immunosuppressive microenvironment. The review also explores different cancer immunotherapy regimens, such as immune checkpoint therapy, neoantigen vaccination, adoptive cell therapy (ACT), oncolytic virotherapy, and nanomedicine, detailing their mechanisms, advantages, and limitations. Despite significant progress, challenges remain, including low response rates, off-tumor toxicity, and tumor heterogeneity. The review emphasizes the importance of understanding tumor and T-cell biology to design more effective immunotherapy regimens and improve therapeutic outcomes.This review provides an in-depth examination of CD8+ T cell-based cancer immunotherapy, highlighting the critical role of CD8+ T cells in anti-tumor immunity and the mechanisms of tumor immune escape. CD8+ T cells, crucial for recognizing and eliminating tumor cells, face challenges from tumor-induced immune evasion strategies. The review covers the life cycle of CD8+ T cells, from their generation and activation to their function and fate. It discusses various mechanisms by which tumors evade CD8+ T cell recognition, including downregulation of immunogenicity, secretion of immunosuppressive factors, expression of immunosuppressive coreceptors, and the formation of an immunosuppressive microenvironment. The review also explores different cancer immunotherapy regimens, such as immune checkpoint therapy, neoantigen vaccination, adoptive cell therapy (ACT), oncolytic virotherapy, and nanomedicine, detailing their mechanisms, advantages, and limitations. Despite significant progress, challenges remain, including low response rates, off-tumor toxicity, and tumor heterogeneity. The review emphasizes the importance of understanding tumor and T-cell biology to design more effective immunotherapy regimens and improve therapeutic outcomes.