The invention provides an automatic power regulating circuit for intermediate frequency signals. The automatic power regulating circuit comprises a protection circuit, a power amplification unit, a voltage control attenuation unit, an intermediate frequency filtering unit, a power divider, a peak detection unit, a sampling maintaining unit, a voltage comparing unit and an overload protection unit. According to the automatic power regulating circuit for intermediate frequency signals and a method, the intermediate frequency signals with a large power changing range can be regulated into a target power range, so that the dynamic range of the power of input radio-frequency signals is greatly enlarged, and the processing capability of an instrument is improved; meanwhile, an overload protection circuit is designed, attenuation of medium frequency signals can be enlarged when power overload occurs, and a rear end channel circuit is effectively protected against damage.