<p>Stretchable triboelectric nanogenerators (TENGs) have garnered significant attention as wearable power sources by enabling the realization of self-powered systems through integration with other wearable platforms. However, achieving intrinsically stretchable TENGs with stable performance under deformation remains a major challenge, particularly in forming robust dielectric/electrode interfaces and fabricating fully stretchable materials. Here, we propose the intrinsically stretchable ionogel-based TENGs (S-iTENG) with a monolithic structure by directly coating silver nanowires (AgNWs) onto free-standing ionogel. The ionogel serves as the substrate, charge-generating, and trapping layer, simplifying device configuration. Its hydrophilic characteristics improve the wettability of AgNWs and their interfacial adhesion. The optimized S-iTENG exhibits a power density of ~109.8 mW·m⁻², excellent stretchability (~195%), and stable operation even under 80% strain. The practical feasibility of the S-iTENG is demonstrated in self-powered sensory platforms. Overall, these results highlight the significance of monolithic, substrate-free S-iTENG as wearable energy harvesters and key components for future wearable electronics.</p>