The utility model relates to surface polishing equipment of a metal round bar sample for a fatigue test, which comprises a bottom plate supporting base, a motor, a coupler, a sample fixture and an abrasive paper fixture, wherein the motor is mounted on the bottom plate supporting base, the coupler is coaxially connected with a motor output shaft, the sample fixture is coaxially arranged with the coupler, and the abrasive paper fixture is mounted on the bottom plate supporting base and positioned below the sample fixture. The sample fixture comprises a first chuck and a second chuck, the first chuck is fixed at the tail end of the coupler, the distance from the first chuck to the second chuck can be adjusted, and the metal round bar sample to be polished is fixed and horizontally clamped between the first chuck and the second chuck. The abrasive paper fixture comprises a sliding seat and abrasive paper, wherein the sliding seat capable of sliding horizontally along the bottom plate supporting base, the abrasive paper is fixed on the sliding seat, and the abrasive surface of the abrasive paper faces the metal round bar sample. When the surface polishing equipment is used, the abrasive paper fixture is controlled to reciprocate axially at a uniform speed so that axial and radial polishing for the sample can be realized, and the polished sample not only can obtain satisfied roughness, but also has no effect on roundness of the round bar sample, so that precision of the fatigue test is greatly improved.