In this paper, we have shown that off-state current in the Tunneling Field Effect Transistor (TFET) can be reduced dramatically by using a low-k oxide and employing gate work function engineering. In order to enhance Ion/Ioff ratio in the TFET, the effect of second gate employing has been investigated, hence using a low-k oxide for the gate near the drain side (Gate2) resulted in omission of fringing field effects. Therefore, the leakage current is decreased. Also a work function engineering method has been employed for the gate near the source (Gate1) to further reduce the off state current.