The real-time monitoring of health conditions of humans is a long-lasting topic, but there are two major challenges. First, many biomedical applications accept only implanted sensors. Second, tissue-like soft sensors often suffer from viscoelasticity-induced signal drift, causing inaccurate measurements. Here, we report a wireless and drift-free sensory system enabled by a low-creep polyelectrolyte elastomer. The system consists of the iontronic pressure sensors incorporating inductance-capacitance (LC) oscillators, exhibiting combined low drift ratio, high