Adipamide used as the curing agent of asphalt-modified epoxy resin was synthesized by esterification and ammonolysis, and its chemical structure was confirmed by the Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (1H NMR and 13C NMR) analysis. The thermal stability, Vicat softening temperature, tensile strength, and Shore D hardness of the cured asphalt-modified epoxy resin were studied by thermogravimetric analysis (TG), Vicat softening tester, tensile tests, and Shore D plastic hardness tester, respectively. The surface morphology of epoxy resin tensile fracture was also observed by scanning electron microscopy (SEM). The Vicat softening temperature of cured epoxy resin decreased from 95 to 64°C with increasing modified asphalt (MA) contents from 0 wt.% to 25 wt.%. The maximum tensile strength of cured epoxy resin reached 45.4 MPa when MA content was 5 wt.% of the whole resin. The Shore D hardness slightly decreased from 86 D to 79 D as the MA was enhanced from 0 wt.% to 25 wt.%. TG results displayed that the thermostable temperature of cured epoxy resin was higher than 280°C.