This paper shows the relevance of an earthquake-stricken area and secondary geological disasters based on the analysis of secondary geological disaster types and harms, and taking an earthquake disaster area as an example, the total value and discharge of debris flow in the area are calculated to determine the risk of debris flow. The vulnerability index is introduced to determine the vulnerability of secondary mountain hazard of each assessment unit. Combined with the actual situation of the studied area, an evaluation model for determining the risk of secondary geological disasters is established based on analytic hierarchy process, and the model can be used to evaluate the risk of secondary geological disasters induced in earthquake disaster areas. Taking the disaster risk triggered by debris flow as an example, an experimental study is performed, and the results indicate that the proposed method in this paper can effectively determine the location of secondary geological disasters induced in the earthquake disaster area. However, the risk assessment of secondary geological disasters induced by longitudinal earthquakes much be studied further.