Abstract: Magnetic particle testing is suitable for detecting surface and near-surface defects of ferromagnetic materials. In the actual inspection, the different workpiece structure or placement needs to be detected from different directions, such as horizontal plane, inclined plane, elevation and partial elevation, etc. The difference of detection orientation and magnetic suspension concentration had a certain impact on the detection results and detection rate. In this paper, through the simulation test of three representative detection azimuths, the influence was verified and four best effect combinations were proposed for reference.