Abstract: To improve potato harvester working efficiency and stability on extreme slopes in hilly and mountainous areas, a self-propelled potato harvester suitable for complex working conditions in hilly and mountainous areas was designed．Based on different working conditions（2°, 15°, 25°）in hilly and mountainous areas, finite element simulation software was employed to analyze structural strength of harvester frame, and modal and vibration analysis was conducted on this basis．Results showed that under three different slopes, the maximum frame deformation were 2.4634, 2.4351 and 2.3236 mm, respectively．The maximum stresses recorded were 167.17, 164.68 and 156.74 MPa, respectively．The maximum deformation and the maximum stresses were relatively small, consistent with actual situation and meeting working requirements in complex hilly and mountainous environments．The first through sixth-order resonance frequencies of potato harvester frame were 18, 19, 20, 21, 21, and 25 Hz, respectively, while vibration source frequency ranged from 4～12 Hz, with no resonance phenomenon occuring．Theoretical reference was provided to ensure smooth operation of potato harvester under complex working conditions in hilly and mountainous areas．