Tissue imaging is usually captured by hospital-based nuclear magnetic resonance. Here, we present a wearable triboelectric impedance tomography (TIT) system for noninvasive imaging of various biological tissues. The imaging mechanism relies on the obtained impedance information from the different soft human tissues. A high-precision signal source is designed on the basis of a composite triboelectric nanogenerator, which exhibits a minimal total harmonic distortion of 0.03% and a peak output signal-to-noise ratio up to 120 decibels. The current density injected into human skin is around 79.58 milliamperes per square meter, far below the safety threshold for medical devices. The TIT system achieves time-resolved tomography of human limbs’ soft tissues, and many appealing functions can be realized by using this wearable system, including the observation of muscle movement, the motion intention recognition, and the identification of pathological changes of soft tissue. Hence, this TIT system with excellent biocompatibility can be integrated with various devices, such as medical-assistive exoskeletons and smart protective suit.