Sand gravel cobble soil is a special subgrade filler. Its engineering properties, construction technology, quality inspection and control are different from those of conventional soil subgrade and rock mixture foundation. Based on different field tests such as sand cone method, differential settlement method and DCP method, it studies the relationship between the times of rolling and compactness when the virtual height of a highway sand gravel and cobble is 30 cm and 40 cm respectively. The results show that when the times of rolling is 4 for sand gravel cobble soil, the calculated compactness for different methods all satisfy the design requirements.