In order to save energy and reduce the pollution of the environment at the same time reduce construction costs, unconfined compression strength of Roadbed-stabilized soil tests are proceed on the base of potential stimulate agent inspired by fly ash and equal quantity replace the cement as the pavement materials use theory of uniform design . Then contrast tests of different level use of exciting agent are proceed. Regression analysis are put down to the results by using SPSS. Optimum mix of cement, fly ash, gravel and aeolianite are obtained when they have same activator. And then the dosage of fly ash are obtained through large number of contrast tests. The results shows that take Cement Fly-ash as the pavement materials is possible in some aeolian soil area where natural sandy gravel lack. It also provides a reference value in the selection of subgrade materials in aeolian soil area.