To broaden the way of utilizing coal waste, explore its application prospect in road engineering, coal waste powder(CWP), coal waste ash(CWA) and limestone(LS) powder were used to prepare asphalt mortar with 5 kinds of filler asphalt ratio. Technical performance tests were conducted to compare the road performance of different asphalt mortar. Furthermore, microscopic tests were conducted to analyse the microcosmic action mechanisms of coal waste powder asphalt mortar. The results show that compared with limestone powder, CWP and especially CWA particles are finer, the surface is rougher and the specific surface area is larger, and which contain more activemineral contents and poring structure, thereby the adhesion of filler asphalt is improved. In addition, the pores of CWP and CWA can absorb light components in asphalt, which resulting the relative contents of colloid and asphaltene in asphalt increase, thus apparently improving the high temperature property and temperature sensitivity of asphalt mortar, but the low temperature performance of asphalt mortar is slightly reduced.