A thin film transistor is provided. The thin film transistor includes an active layer, and the active layer includes a plurality of stacked structures, and each of the stacked structures includes: a N-layer indium oxidation layer; a gallium oxidation layer, the gallium oxidation layer is provided on the indium oxidation layer of the N-layer indium oxidation layer; and a zinc oxidation layer is provided on the gallium oxidation layer. These stacked structures improve the performance of the thin film transistor. A preparation method of the thin film transistor and a display panel containing the thin film transistor is also provided.