The invention relates to an AGC device of digit TV receiver, which comprises: a passband/baseband data selector for selecting the input passband signal or feedback baseband signal; an external AGC device (automatic gain control) for using the input signal power without DC component and the preset reference signal to check the gain error, and based on the AGC step signal, to output the RF AGC control signal and IF AGC control signal to control the external gain; and an internal AGC device that driven by said AGC step signal and using the selected signal of passband/baseband data selector to control the internal gain of receiver. |