The advent of the information age has promoted the development of smart wearable electronics for acquiring real-time data, such as smart bracelets, real-time health monitors, electronic skins, and smart clothes, [1][2][3][4][5][6][7][8][9] which has in turn promoted the development of power supply systems with high operational safety, long cycle life, high energy, and excellent deformability. Among recently developed flexible power supplies, [10][11][12][13][14] flexible lithium-ion (Li-ion) batteries have been dominantly employed in wearable electronics because of competitive chargedischarge efficiency (≈90%), high energy density (≈400 W h kg −1 ), durable cycling life (≈5000 cycles) and mature Li-ion battery infrastructure. [15] Moreover, wearable fiber Li-ion batteries can be woven into textiles, offering a convenient way to power wearable electronics. [16][17][18] Nonetheless, the safety and environmental risks caused by the usage of flammable/ toxic organic electrolytes restrict the further advance of Li-ion batteries and make them unsatisfied to be integrated with wearable electronic devices in proximity to the human body. [15,19] Further efforts are highly demanded to explore alternative power systems with promising energy density, reliable discharge-charge characteristics, long operation life, and good safety.In recent years, metal-air batteries have received widespread attention because of their remarkable theoretical energy density, environmental-friendliness, low fuel cost, and superior safety. [20][21][22][23] In particular, their unique half-open systems can continuously utilize the oxygen from ambient air instead of storing gaseous oxygen in closed systems, thus the required mass and volume of the air electrode can be largely minimized, resulting in high theoretical energy densities. [24] Compared to the theoretical energy density of Li-ion batteries with a closed system (460 Wh kg −1 ), lithium-air (Li-air) batteries exhibit much higher theoretical energy density (≈3500 W h kg −1 , based on the discharge product of Li 2 O 2 ). [25,26] Flexible wearable metal-air batteries, combining the flexible deformation feature and the high theoretical energy density, have become attractive energy supply systems for wearable electronic devices. Since 2015, wearable metal-air batteries (i.e., zinc-air (Zn-air), Li-air, aluminum-air (Al-air), sodium-air (Na-air), potassium-air (K-air), With the increasing popularity of personal wearable electronic devices used for healthcare, entertainment, and sports applications, the corresponding energy supply and space adaptability of devices are required to meet higher standards. Owing to large energy densities and intrinsic safety, wearable aqueous metal-air batteries have shown great potential to be energy storage/ conversion integrated systems for wearable electronic devices characterized by long-term low-power operation. In contrast to non-aqueous electrolytes, aqueous-based electrolytes exhibit greater ionic conductivity, higher operational safety, lower cost, and super...