Abstract: Taking the expansive soil of Xuhe River slope in Gaochun County, Jiangsu Province as an object, based on the current specification of engineering and the research results of measurement method for loaded linear expansive ratio used by some researchers, the problems of the current two methods are analyzed and an improved method for linear expansive ratio measurement is put forward. The experiment of loaded linear expansive ratio and expansive force was conducted by different methods and the results were compared. It indicated that in the same initial state, the linear expansive ratio measured by the improved method is the largest, while the one measured by the methods suggested by some researchers is the minimum, and that measured by the geotechnical specification method is in between; the expansive ratio measured by the three methods can be expressed by one formula; the three measurement methods give bigger different results of linear expansive ratio when the expansive soil is in smaller dry density and overburden pressure.