The invention discloses a channel selection method of a multi-narrowband aggregation terminal. The channel selection method comprises the following steps of S1, enabling each narrowband channel to estimate the channel quality of each frequency point sub-channel according to a downlink reference signal; S2, converting into a link transmission rate according to the channel quality; S3, selecting a sub-channel with the highest transmission rate; S4, judging whether the selected sub-channel is repeated with sub-channels selected by other narrow-band channels or not; S5, if the sub-channels selected by all the narrow-band channels are different, entering the step S6, otherwise, entering the step S7; S6, taking the sub-channels selected in the step S3 or the step S7 as communication frequency points of corresponding narrow-band channels, and then entering the step S8; S7, performing joint sub-channel selection on the narrow-band channels with the same sub-channel selection, and then enteringthe step S6; and S8, enabling each narrow-band channel to initiate a random access process on the frequency point determined in the step S6 and perform data transmission. According to the present invention, the data transmission rate and the transmission stability of the aggregation terminals are greatly improved.