The study of wearable devices has become a popular research topic recently, where high‐sensitivity, noise proof sensing mechanisms with long‐term wearability play critical roles in a real‐world implementation, while the existing mechanical sensing technologies (i.e., resistive, capacitive, or piezoelectric) have yet offered a satisfactory solution to address them all. Here, we successfully introduced a flexible supercapacitive sensing modality to all‐fabric materials for wearable pressure and force sensing using an elastic ionic–electronic interface. Notably, an electrospun ionic fabric utilizing nanofibrous structures offers an extraordinarily high pressure‐to‐capacitance sensitivity (114 nF kPa−1), which is at least 1000 times higher than any existing capacitive sensors and one order of magnitude higher than the previously reported ionic devices, with a pressure resolution of 2.4 Pa, achieving high levels of noise immunity and signal stability for wearable applications. In addition, its fabrication process is fully compatible with existing industrial manufacturing and can lead to cost‐effective production for its utility in emerging wearable uses in a foreseeable future.