<p>Flexible and wearable nanogenerators (NGs) have been spotlighted as next-generation healthcare electronics by enabling self-powered operation and convenient telemedicine. NGs based on mechanisms of piezoelectricity and triboelectricity with novel strategies will pave the way for an innovative healthcare system. Here, representative healthcare NGs are reviewed in terms of materials engineering, structure designs, and on-skin medical applications. This article introduces the polymer dielectric materials and stretchable and wearable materials for piezoelectric and triboelectric NGs, as well as stretchable conductors for electrodes. To maximize power output on human skins, high-efficient NGs have been designed based on electrode structure, self-powered fabric, and encapsulated perovskite membrane. We believe a comprehensive understanding of on-skin healthcare NGs would benefit all humankind by realizing a smart telemedicine platform capable of real-time detection/diagnosis, medical treatment, and signal communications.</p> Graphical abstract <p></p>