The present invention discloses a strip-shaped gate-modulated tunneling field effect transistor with double-diffusion and a preparation method thereof, belonging to a field of CMOS field effect transistor logic device and the circuit. The tunneling field effect transistor includes a semiconductor substrate, a highly-doped source region, a highly-doped drain region, a double-diffusion source region, a gate dielectric layer, and a control gate, wherein the control gate has a strip-shaped structure with a gate length greater than a gate width, and at one side thereof is connected to the highly-doped drain region and at the other side thereof extends laterally into the highly-doped source region; a region located below the control gate is a channel region; the gate width of the control gate is less than twice width of a source depletion layer; the double-diffusion region has the same doping region as the highly-doped source region and the double-diffusion region has the same doping type as the highly-doped drain region; and the channel region located below a portion of the control gate portion in the highly-doped source region has double-diffusion source doped impurities. The TFET device according to the invention improves its performance, and the preparation method thereof is simple.