A projector and a drive circuit thereof are provided. The projector includes a light source and a drive circuit. The light source includes at least one red light diode, at least one green light diode, at least one first blue light diode and at least one second blue light diode. The drive circuit includes a red light drive circuit, a green light drive circuit, a first blue light drive circuit and a second blue light drive circuit. The green light drive circuit outputs a green light drive signal to the green light diode according to a green light control signal. The second blue light drive circuit outputs a second blue light drive signal to the second blue light diode according to a second blue light control signal. The second blue light control signal and the green light drive signal have synchronous pulse.