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DOI: 10.1002/aenm.201902769 improved user experience. Consequently, consumer electronics has found ubiquitous applications in daily life, including entertainment, communications, and home–office activities, with the field of applications being expanded as the technology further develops. In particular, as the technologies of consumer electronics, high-volume data analysis, and medical science converge, much effort has been devoted to exploring the applications of electronic devices in health monitoring in recent years.[1,2] Health monitoring devices offer the opportunity to continuously collect data on health conditions, including vital signs,[3,4] body motions,[5] metabolism status,[6] and even biomarker levels.[7] These data can be analyzed in real time, providing close monitoring of the health conditions and in-time suggestions on interventions if necessary. Given the aging problem around the globe, especially in developed countries, and the resultant increasing cost on healthcare, health monitoring devices can drastically reduce the burden on ambulatory care as well as inpatient care by providing health condition alert and early diagnosis.[2] Health monitoring devices typically comprise three parts, namely sensing unit, data transmission unit, and power unit.[4] Sensing unit senses the input parameters, such as pulse, blood pressure, and temperature, and then converts the input into electrical signals as output, which are preprocessed and transmitted by the data transmission unit to another device, such as cloud or cell phone, for further analysis and interpretation. Both the sensing and data transmitting process require the powering from a battery or alike. Compared to other electronic devices, health monitoring devices have special requirements on the power unit. First, the power unit as well as the device itself need to have good stretchability, to ensure conformable contact on the body and consistent sensing performance. Second, since the device is likely to be in contact with bodily parts, the power unit and the device need to possess good biocompatibility to avoid unwanted immune response and other adverse effect. Lastly, for power unit in particular, given that oftentimes health monitoring devices have only minute power consumption, it is amenable to incorporate an energy harvesting unit to charge the power unit with energy from intermittent body motion, which requires a fast charging rate.[8] Emerging health monitoring bioelectronics require energy storage units with improved stretchability, biocompatibility, and self-charging capability. Stretchable supercapacitors hold great potential for such systems due to their superior specific capacitances, power densities, and tissue-conforming properties, as compared to both batteries and conventional capacitors. Despite the rapid progress that has been made in supercapacitor research, practical applications in health monitoring bioelectronics have yet to be achieved, requiring innovations in materials, device configurations, and fabrications tailored for such applications. In this review, the progress in stretchable supercapacitor-powered health monitoring bioelectronics is summarized and the required specifications of supercapacitors for different types of application settings with varying demands on biocompatibility are discussed, including nontouching wearables, skin-touching wearables, skin-conforming wearables, and implantables. The perspective of this review is then broadened to focus on integration of stretchable supercapacitors in bioelectronics and aspects of energy harvesting and sensing. Finally further insights on the existing challenges in this developing field and potential solutions are provided.