The invention discloses a welding position automatic adjusting device suitable for simulation welding equipment. The welding position automatic adjusting device comprises a horizontal base, a linear sliding table, a horizontal sliding seat, an R-axis rotator, a motion module, a mated driver and a control panel, wherein the linear sliding table is vertically fixed to the rear end part of the horizontal base; the horizontal sliding seat is clamped and embedded in a vertical guide rail of the linear sliding table; the R-axis rotor is horizontally arranged on the horizontal sliding seat; the motion module is connected with the output shaft end of the R-axis rotator; the motion module comprises a gathering frame formed by a flange end plate, a left side plate and a right side plate, an A-axis rotator which is fixed to the upper part of the left side plate in a cantilever mode, a fixer installation shaft which is horizontally arranged at the lower parts of the left side plate and the right side plate in a penetrating way, and a workpiece fixer which is arranged on the fixer installation shaft in a sleeving way; belt wheels are arranged on the output shaft end of the A-axis rotator and the left shaft end of the fixer installation shaft. According to the device, which is capable of realizing all-directional adjusting and automatic adjusting on a welding position, provided by the invention, the device has the advantages of strong expandability, high position adjusting efficiency, simpleness in operation, safety in use, concision and attractiveness.