In order to characterize the impacts of key factors on the low-temperature fracture performance of dense-graded asphalt concrete, the virtual bending fracture test is simulated by using the discrete element method (DEM) and emulation software PFC3D (particle flow code in three-dimension). A virtual specimen generation procedure consisting of aggregate gradation, irregular clumps, asphalt mortar and air void content is performed based on the random generation algorithm and irregular coarse aggregates library. Then, the virtual fracture test is conducted after adding the micro mechanical contact models to the specimen, and the validity of virtual modeling is verified by the comparison of simulation test data and lab test data. Additionally, an orthogonal test is designed to investigate the impacts of the volume fraction of coarse aggregates and air voids, stiffness of coarse aggregates and asphalt mortar, internal bond strength of asphalt mortar and distribution of coarse aggregates and air voids on low-temperature fracture performance based on virtual simulation. The results show that all the factors have effects on fracture performance to various degrees, while the value of the bond strength of asphalt mortar is found to be the most important determinant of tensile strength and strain-energy density. The volume fraction of coarse aggregates is considered to be the most important determinant of tensile strain. Therefore, to obtain a high low-temperature fracture performance of dense-graded asphalt concrete, it is important to consider the microstructure and properties of asphalt mortar and aggregates.