This paper presents a new dimmer using only two active switches for AC LED lamp. The control method of the proposed dimmer is pulse width control (PWM) method. Compared with the conventional phase- controlled dimmer, the proposed PWM dimmer can produce sine wave and it does not cause harmonics problem. Furthermore, the proposed control method does not amplify the light flicker due to independence of the input voltage. Therefore, the proposed PWM dimmer can be used as the AC LED lamp's dimmer instead of the conventional phase-controlled dimmer. The experimental result shows that the proposed PWM dimmer has good performances.