Abstract: Taking the high cap foundation of rock-socketed pile group using concrete filled steel tubular composite pile in Fujian offshore wind farm as the research object, the vertical compressive bearing characteristics and failure mechanism of rock-socketed pile group were studied by scale model test, and compared with rock-socketed single pile. The results show that in the early stage of loading, the overburden and bedrock between the concrete filled steel tubular composite pile group and the pile as a whole bear the upper compressive load together, which leads to the smaller increase of the axial force at the pile end of the pile group than that of the single pile, and the resistance at the pile end is limited, the downward stress is more difficult to diffuse than that of the single pile. In the later stage of loading, the connection cracks appear between the piles, which weakens the bearing capacity of the soil between the piles, and makes the pile end resistance and end resistance ratio of the pile group increase obviously. In addition, in order to avoid the influence of pile group effect, the pile spacing of concrete filled steel tubular composite piles should be above 3 times the pile diameter.