Abstract: The Qinggaoni from the mausoleum of Yue Kindom was studied to improve the engineering quality through some tests such as liquid limit test, plastic limit test, the compaction test. Tests showed that it is silt and its water content is 16.7% when it is the maximum dry density. Tests also showed that the compaction coefficient of backfilled Qinggaoni is above 0.90. which implies its compaction coefficient is satisfied with strength requirement.