In recent years, ion-gating devices have been used in artificial neuromorphic computing and achieved high performance for time-series data processing. However, the origin of such performance still needs to be clarified. In this study, we fabricated an all-solid-state redox device with functional material Fe3O4 and Li-ion conducting solid electrolytes, and the transient response of the electrical resistance of the Fe3O4 thin film to time-series data input was investigated. The transition between high and low electrical resistance states was asymmetry, and residual Li-ion in the thin film led to a hysteresis effect. These unique features, which is induced by ion-electron dynamics coupling, contributes to the high performance of physical reservoir computing utilizing ion-gating device.