Graded highway is an important object of regional toughness evaluation. It is necessary to evaluate the toughness of graded highway sections in disaster areas after earthquake disasters, so as to formulate the best emergency rescue plan. There are many aspects of the impact of earthquake disasters on the toughness of graded highway sections. This paper further analyzes the factors of the impact of earthquake disasters on the capacity of graded highway sections, and concludes the disaster factors of the impact of earthquake on the toughness of graded highway sections. The disaster factors of decreasing capacity of grade highway sections caused by earthquake mainly include: underground void, landslide, collapse, debris flow, ground crack, ground subsidence, ground collapse, surface foreign. These disaster factors are important aspects of earthquake disaster resilience evaluation of graded highway sections. Single consistent disaster factors can be combined with their own characteristics to establish the corresponding evaluation criteria. In this paper, the single consistent disaster factors can be graded and evaluated. According to the traffic capacity of graded highway sections, they can be classified into three categories: smooth passage, slow passage and difficult passage. The evaluation index of each level is consistent with that of the single consistent disaster factor. In the process of grade highway section toughness evaluation, the number of lanes is an important index affecting the toughness of the section. The weight coefficient can be used to evaluate the seismic toughness of grade highway according to the number of lanes of the grade highway. The research results of this paper are of great significance to the formulation of a dredging plan in emergency rescue after the earthquake.