The invention discloses a micro-strip miniature equational power divider based on a stepped-impedance artificial transmission line. The power divider comprises a signal input port and two signal output ports, wherein the signal input port is connected with one signal output port by an artificial transmission line; the artificial transmission line comprises two uniform transmission lines, two lowerhigh-impedance transmission lines, two lower low-impedance transmission lines, two middle high-impedance transmission lines, two middle low-impedance transmission lines, two upper high-impedance transmission lines, an upper low-impedance transmission line and an interdigital capacitor structure; and the two uniform transmission lines, the two lower high-impedance transmission lines, the two lowerlow-impedance transmission lines, the two middle high-impedance transmission lines, the two middle low-impedance transmission lines, the two upper high-impedance transmission lines, the upper low-impedance transmission line and the interdigital capacitor structure consist of the stepped-impedance artificial transmission line. The power divider replaces a quarter-wavelength transmission line in atraditional Wilkinson power divider with the stepped-impedance artificial transmission line; and the size is reduced under the condition that the performance of the power divider is constant.