In recent decades, immunotherapy has emerged as a promising approach in cancer treatment. However, tumor-specific immunity is often insufficient to achieve effective therapeutic outcomes. The accumulation of various genetic and epigenetic alterations within cancer cells, combined with the presence of multiple inhibitory factors, such as immunosuppressive cytokines, myeloid-derived suppressor cells, and regulatory T cells, suppresses immune responses within the tumor microenvironment, allowing cancer cells to evade immune surveillance. The development of nanoparticle-based drug delivery systems offers the potential not only to enhance the efficacy of immunotherapy but also to inhibit key factors that contribute to immune suppression in the tumor microenvironment, providing a promising strategy to improve cancer treatment outcomes. Biomimetic nanoparticles, inspired by natural cells and designed to mimic their structure and function, exhibit enhanced properties and transformative potential in cancer immunotherapy. Advantages of biomimetic nanoparticles over conventional nanocarriers include biocompatibility, high targeting ability, immune evasion, biodegradability in living tissues, low immunogenicity, and minimal biological toxicity. This article provides a comprehensive review of biomimetic nanoparticles, including their types and detailed applications in cancer immunotherapy. Additionally, various methods for synthesizing these nanoparticles, along with their advantages and challenges in cancer immunotherapy, are discussed. Finally, future perspectives and recent advancements in this field are presented.