Experimental research on road performance of drydesulphurized fly ash had been done. Results show that drydesulphurized fly ash has poor compatibility with lime but has good compatibility with cement. Stabilized crush stone used cement and drydesulphurized fly ash as binder material has enough mechanical strength and water stability to meet the requirement of road base course. It almost has no influence on its strength when rolled in 8 h after mixing and it is good for practical application.