Cell membrane vesicles (MVs), particularly mammalian-derived vesicles (MMVs) and bacterial-derived vesicles (BMVs), have emerged as effective platforms for the treatment of infectious diseases and cancer. Through engineered modifications, the functionality of these MVs can be further enhanced, endowing them with properties such as improved targeting, stability, and biocompatibility. As research into their characteristics continues to advance, the clinical application potential of these vesicles is becoming increasingly evident. In this chapter, we focus on the application of engineered membrane vesicles (EMVs) technologies in cancer and infectious disease therapies. First, we summarize and compare various MVs functionalization methods, including physical, chemical, and biological approaches. We also provide an overview of MVs production and engineering techniques, discussing strategies for improving MVs yield and reducing toxicity. Next, we examine the recent progress in the use of EMVs as nanovaccines and therapeutic platforms for treating infectious diseases and cancer. Finally, to further advance the clinical application of EMVs, we address the challenges and prospects associated with their clinical translation, offering insights and recommendations to shape future research and applications in this field.