The invention provides a method for simulating influence of a high-voltage AC power transmission line on a buried steel pipeline. Three magnetic leakage strengthening cables are arranged according to a high-voltage AC power transmission line three-phase transmission mode via an insulating bracket to simulate three-phase AC of the high-voltage power transmission line, and the three magnetic leakage strengthening cables are distributed above the outdoor buried pipeline to simulate the high-voltage power transmission line. Bracket support of the insulating bracket is controlled by a stepping motor. A cross angle of the three-phase magnetic leakage strengthening cable and the buried pipeline is adjusted, and the size of the cross angle is accurately controlled by the stepping motor. Overhead height of the magnetic leakage strengthening cable is adjusted by the bracket. Alternating current is adopted to act as an interference excitation source, and magnetic field intensity generated by the three-phase magnetic leakage strengthening cable is adjusted via adjusting the size of alternating current flowing through the cable. Simulation of interference of the high-voltage AC power transmission line with different voltage levels on the buried pipeline can be realized so that accurate control of change of the three-phase transmission arrangement mode of the three magnetic leakage strengthening cables and the cross angle between the buried pipeline and the cables can be realized.