The invention discloses an intelligent method for scanning channels and a relative device. The invention is used for searching the center frequency of the channel of a video signal and a relative symbol rate. The intelligent method for scanning channels comprises: scanning the video signal for carrying out frequency spectrum analyzing, obtaining the central frequency and a plurality of crude regulated bandwidths according to the frequency spectrum analysis of a plurality of bandwidths in the video signal; utilizing the density of a power frequency spectrum and the crude regulated bandwidths to obtain the accurate symbol rate.