Pure natural material-based energy harvesters are promising to become green energy sources for constructing self-powered systems, as these devices can produce renewable clean energy by collecting the low-quality mechanical energy or electromagnetic energy from the ambient environment without causing pollution problems. In this work, a natural leaf-made electromagnetic energy harvester (NLMEEH) for harvesting the ambient electromagnetic energy is proposed mainly with environmentally degradable natural fresh leaves. With basic working mechanism of electromagnetic coupling effect, the NLMEEH can produce peak output power density up to ∼4.52 mW/m, and the energy generating process will continue stably until the natural leaves wither. As typical applications, the energy harvested by the NLMEEHs can be stored or is utilized to power a digital clock and a temperature–humidity sensor, indicating the potential applications in green energy harvesting for distributed sensors in Internet of Things (IoT).