Abstract: With the cast steel track plate of a small tonnage crane as the research object, the surface layer microstructure after wear, wear behavior of the track plate were studied by sliding wear test under different loads (5–35 N). The results show that under 5 N load, only a plastic rheological layer with thickness of about 10 μm was formed on the surface of the track plate. Under 15–35 N loads, the surface deformation layer was composed of a fine crystal layer on the surface and a plastic rheological layer on the subsurface, and there were micro-cracks in the fine crystal layer. With increasing load, the thickness of the surface deformation layer increased. With the increase of load, the wear mass loss of the track plate increased. Under 5 N low load, the wear surface of the track plate was relatively flat, and the wear mode was slight abrasive wear. When the load was higher than 5 N, spalling pits appeared on the wear surface, and the wear mode was abrasive wear and fatigue wear.