The invention relates to a combined AM channel search method. The method comprises the following steps: S10, turning to specific frequency, and performing reset modulation; S20, detecting a signal level, detecting whether a plurality of radio signals exist under the frequency, and executing step S30 if the plurality of radio signals do not exist; S30, reading a modulation index within a first preset time, and obtaining a maximum value and a minimum value of the modulation index; and S40, calculating a minimum index difference, and judging whether the current frequency channel is a good channel according to the size of the minimum index difference. The combined AM channel search method has the following beneficial effects: the quality of the channel signal is effectively judged by combining the signal intensity with the signal bandwidth; and 2, the channel search efficiency is greatly improved.