Research on aqueous zinc-ion batteries is still in its initial stages owing to the limited choice of cathode materials, especially those having tunnel structures with high capacity and fast kinetics. Furthermore, their zinc ion storage mechanisms are not well established as yet. Here, a novel in situ electrochemical lattice distortion of vanadium trioxide (V2O3) is demonstrated. The obtained defect-rich V2O3 is applied as a cathode for ultrafast Zn2+ storage. Operando X-ray diffraction and operando Raman spectroscopy corroborate the unique lattice conversion reaction of V2O3 during the initial charging process. Transmission electron microscopy and X-ray photoelectron spectroscopy further demonstrate the stability of the main crystal planes of V2O3 during the initial lattice distortion and subsequent zinc ion storage processes. This unique in situ electrochemical lattice conversion reaction allows V2O3 to achieve a high capacity of 382.5 mAh g���1, remarkable rate performance (154.3 mAh g���1 at 51.2 A g���1), and high energy and power densities (139��Wh kg���1 at 46 KW kg���1), revealing the potential of tunnel-type cathodes via an in situ electrochemical lattice distortion reaction to achieve ultrafast zinc ion storage with high capacity.