In order to overcome the problem of slag cement stabilized macadam early strength is insufficient, the sodium hydroxide and sodium silicate two alkaline activator activity of slag cement excitation based on the single doped test results blending out a composite alkali activator, and studied the compound alkali exciting agent of water stable macadam base without side limit compression strength, splitting tensile strength, flexural strength, compressive modulus of resilience and dry shrinkage performance of. Experiment results show that the incorporation of sodium hydroxide or sodium silicate can effectively stimulate the activity of slag cement, two reasonable dosage respectively 6% and 4%, according to the reasonable dosage of compound compound alkali excitant has more excellent than the single doped effect; the compound alkali excitant better provided high specimen without side unconfined compressive strength, splitting tensile strength, flexural strength, compressive modulus of resilience, but the dry shrinkage performance produced adverse effects.