The rapid development of wearable devices and soft robotics has an urgent demand for polymer conductors with a switchable adhesion property. Herein, we report a supramolecular ionogel (SIG) that can reversibly switch between adhesion and debonding to various substrates. The on/off switchable adhesion of SIG is attributed to phase separation induced by the aggregation of polymer chains and the formation of a lubricating layer, which impairs the contact between polymer chains and substrates, thus weakening interfacial interaction. The phase separation ionogel (PSIG) is highly sensitive to humidity, leading to the debonded PSIG instantly transforming into the adhesion-hydrated ionogel (HIG) owing to the disruption of phase structure. Based on the switchable adhesion property, this multiresponsive ionogel shows potential applications as a fire alarm and intelligent conductive tape. This work provides a simple method for developing a switchable adhesion ionic polymer conductor and broadens the application of the ionogel in flexible devices.