Immunotherapy has revolutionized cancer treatment, demonstrating remarkable clinical efficacy. A particularly promising modality is adoptive immune cell therapy, a critical component of cancer immunotherapy that provides a highly targeted, personalized strategy by harnessing the immune system to combat cancer. Its potential for long-lasting immune surveillance and its success in treating challenging cancers highlight its vital role in modern cancer therapy. Membrane engineering of adoptive immune cells further enhances the precision, efficacy, and safety of this approach. By modifying the surface characteristics of immune cells, researchers can overcome key challenges, including tumor immune evasion, limited cell persistence, and off-target effects. This membrane engineering approach demonstrates significant potential to enhance adoptive cell therapy efficacy while broadening its therapeutic scope across diverse malignancies. This chapter will explore both genetic and non-genetic methods used in immune cell membrane engineering, demonstrating how these advancements enable the development of personalized therapies. These therapies may substantially enhance outcomes for patients across a diverse array of cancer types, including those that are currently difficult to treat.