Pile groups are widely utilized as foundations for various onshore and offshore structures. When positioned adjacent to or directly on a slope, the axial bearing capacity of both single piles and pile groups decreases. Reinforcing the underlying soil with geogrids is an effective strategy for enhancing bearing capacity; however, the influence of geogrid-reinforced slopes on pile group performance has not been comprehensively examined. This study employs physical model tests to assess the impact of geogrid reinforcement on the bearing capacity of pile groups located at the crest of a sandy slope. In this research, a 2×2 pile group with steel piles of 18 mm diameter and 400 mm embeded length was modeled on the crest of a medium-density sandy slope reinforced with geogrid, and the effects of factors such as the number of geogrid layers, the distance of the first geogrid from the horizontal surface, the spacing between geogrid layers, and geogrid dimensions on axial bearing capacity, tilting, and horizontal displacement of cap were investigated.The experimental results indicate that the optimal placement of the first geogrid layer and optimal distance between geogrid layers is 0.66 times the pile cap width, with three geogrid layers providing the most effective reinforcement. Additionally, geogrid reinforcement significantly reduces horizontal displacement and tilting and with increasing geogrid dimensions, the bearing capacity of the pile group increases.