Expansive siol is distributed widely along He-Liu expressway.The comprehensive evaluating indicators of the expansive soil on engineering characteristics,such as minal components,the basic index of physical appearance,the compacted property,swell-shrink characteristics and strength and so on,are obtained by spot sampling and laboratory tests.The optimum moisture contents of weak and meduim expansive soils are determined under the different compacted power.The reliable evidence is provided for the scientific improvement in expansive soil area.