This paper presents the beam emission test of a triode-type Pierce gun pasted with a carbon nanotube (CNT). A DC emission current from the gridded-CNT cathode was measured to be 4.2 mA where the applied cathode voltage is -0.86 kV, grid and anode are ground, and cathode-to-grid distance is 200 mum. We also examined the mode field emission characteristics with two accelerating stages. The pulsed current emission of 2.8 mA was measured where a cathode voltage is -4 kV, cathode-grid potential difference is 1.38 kV, and pulse width is 100 mus