This review discusses the application of nanotechnology in enhancing cancer immunotherapy by overcoming immunosuppression. The authors summarize various nanomedicine approaches that target tumor immunosuppression, including nanocarriers for delivering immunomodulatory agents, nanoparticles that modulate tumor-associated macrophages (TAMs), and nanomaterials that enhance immune responses. Key nanomedicine systems include PHNPs@DPA-S-BSA-MA@3-MA, IL-12/α-TOS-loaded TRN, TNPs for co-delivery of IL-12 and doxorubicin, BLZ945/Sel NPs, P/T@MM NPs, R848@LNPs, MIX-NPs, tLyp1-CH NPs, Cur NPs, IR780/Met NPs, SHP-1/Cbl siRNA LNPs, and others. These nanomedicine systems aim to modulate the tumor microenvironment, enhance immune cell function, and improve the efficacy of immunotherapy. The review highlights the importance of targeting immunosuppressive mechanisms, such as TAM polarization, Treg cell regulation, and checkpoint inhibition, through nanotechnology. It also discusses the potential of nanomedicine to overcome barriers in immunotherapy, such as poor drug delivery, immune evasion, and tumor microenvironment resistance. The review emphasizes the need for further research to optimize nanomedicine for cancer immunotherapy.This review discusses the application of nanotechnology in enhancing cancer immunotherapy by overcoming immunosuppression. The authors summarize various nanomedicine approaches that target tumor immunosuppression, including nanocarriers for delivering immunomodulatory agents, nanoparticles that modulate tumor-associated macrophages (TAMs), and nanomaterials that enhance immune responses. Key nanomedicine systems include PHNPs@DPA-S-BSA-MA@3-MA, IL-12/α-TOS-loaded TRN, TNPs for co-delivery of IL-12 and doxorubicin, BLZ945/Sel NPs, P/T@MM NPs, R848@LNPs, MIX-NPs, tLyp1-CH NPs, Cur NPs, IR780/Met NPs, SHP-1/Cbl siRNA LNPs, and others. These nanomedicine systems aim to modulate the tumor microenvironment, enhance immune cell function, and improve the efficacy of immunotherapy. The review highlights the importance of targeting immunosuppressive mechanisms, such as TAM polarization, Treg cell regulation, and checkpoint inhibition, through nanotechnology. It also discusses the potential of nanomedicine to overcome barriers in immunotherapy, such as poor drug delivery, immune evasion, and tumor microenvironment resistance. The review emphasizes the need for further research to optimize nanomedicine for cancer immunotherapy.