AbstractPersonal electronic devices are moving toward an era in pursuit of wearability and versatility enabling a wide range of healthcare, entertainment and sports applications. Conventional power source with bulky and rigid structure becomes a bottleneck for the rapid advancements of wearable smart electronics. To meet the requirement of next‐generation wearable electronics, power supplies with high flexibility, bendability, and stretchability have received extensive attention. In this review, requirements of flexible and wearable power sources in terms of the flexible battery configuration design, flexible materials, energy density and other request are highlighted. Several promising power supplies (e. g., metal−sulfur batteries, metal−air batteries, energy storage and conversion integrated devices) for the application of wearables are discussed in detail. Furthermore, discussions are presented on the remaining challenges and some possible research directions to establish a perspective for practical applications of power sources for wearable electronics in the near future.