Recently, immunomodulatory nanomaterials have gained immense attention due to their involvement in the modulation of the body’s immune response to cancer therapy. This book highlights various immunomodulatory nanomaterials (including organic, polymer, inorganic, liposomes, viral, and protein nanoparticles) and their role in cancer therapy. Additionally, the mechanism of immunomodulation is reviewed in detail. Finally, the challenges of these therapies and their future outlook are discussed. We believe this book will be helpful to a broad community including students, researchers, educators, and industrialists.