The effect of three types of additives, including cement(C), hydrated lime(L) and hydrated lime slag powder(LS) on the pavement performance of cold recycled asphalt emulsion mixture was investigated. Interface microstructure between new old mastics in cold recycled asphalt emulsion mixture with cement was observed by scan electron microscopy, and then the strength improvement mechanism of cold recycled asphalt emulsion mixture by additives was analyzed. The test results show that the addition of cement can improve the indirect tensile strength, rutting resistance, water resistance and fatigue life of cold recycled asphalt emulsion mixture best, followed by hydrated lime slag powder, hydrated lime is the last. The stiffness modulus of new mastic formed by hydrate products of cement or hydrated lime slag powder with asphalt emulsion is similar with that of old mastic(aged asphalt mastic). Hydrate products has the bridge effect between new old mastics, promoting the loading coordination and increasing the interface adhesive between new old mastics, thus， the strength and pavement performance of cold recycled asphalt emulsion mixture can be improved.