An enhanced tunnel field effect transistor includes a substrate, a layer of P-I-N structure, a hetero-material layer, a gate dielectric layer, a gate structure and a spacer, in which the layer of P-I-N structure is disposed on the substrate, the hetero-material layer is disposed on portion of the layer of P-I-N structure, the gate dielectric layer is disposed on the hetero-material layer, the gate structure is disposed the gate dielectric layer and a spacer is disposed on a sidewall of the hetero-material layer, the gate dielectric layer, and the gate structure. The hetero-material layer can increase the tunneling efficiency of the enhanced tunnel field effect transistor to increase the conductor current to improve the enhanced tunnel field effect transistor performance.