In this letter, a current driving method by using a field-effect transistor (FET)-modulated structure for a carbon-nanotube field emission device (FED) is reported. This device can obtain a stable large emission current modulated value by tunneling the gate voltage of the metal–oxide–semiconductor FET, i.e., from 2 to 128 (the anode voltage is 1000 V). Moreover, a subpixel FED and a periphery circuit are also designed. This device can dramatically produce a working pulse emission current (peak current: 350 ) by controlling a low-voltage high-speed pulse signal (peak: 22.5 V). Compared with the previous triode FEDs, this FET-modulated device has more advantages in driving circuit design. If the integrated process for this device can be realized, it will promote the FED's application to launch on the market.