Asphalt mortar plays an essential role of filling voids, adhering coarse and fine aggregate and transferring loan in asphalt concrete which has important effect on asphalt concrete' structure and strength.This paper studied the tensile strength of asphalt mortar by taking the factors of filler type, filler concentration, test temperature as influence factor by orthogonal design and got the primary and secondary order and variation law by regression analysis and variance analysis and projection pursuit.Fill concentration has prominent impact on tensile strength. The tensile strength increases markedly with the increase of filler concentration.The test temperature and filler type have notable influence on tensile strength.The tensile strength increases with the decrease of test temperature.The stronger the alkaline of filler,the tensile strength of asphalt mortar is greater.