In order to study different powder/asphalt ratios effect on high temperature performances of mortar, this paper chooses limestone as the filler, and powder/asphalt ratio is 0.2, 0.4 ,0.6, 0.8. Mortar high temperature performance evaluation index selects Fail temperature and ZSV through DSR test. The test results show that with the increase of powder/asphalt ratio, Fail temperature and ZSV value of the mortar increase gradually, and the amplitude is larger. High temperature performance of the mortars improves obviously. By using environmental scanning electron microscopy search for those mortars, the results show that crumb rubber modified asphalt mortar of powder is smooth and delicate, the powder is covered uniformity by crumb rubber.