The road systems in the metropolitan areas may be damaged during an earthquake, causing difficulties to disaster response and rescues. This study performed a risk analysis of an earthquake scenario to evaluate the vulnerability of road systems and the impacts of traffic failure. A case study of Taichung city was included to discuss the failure risk of emergency evacuation. Data for Taichung city buildings and road networks were analyzed. A hybrid-assessment procedure of road failure risk analysis had been developed based on the TELES model and the building vulnerability assessment. The proposed analysis procedure includes simulation of a strong motion using the TELES model; analysis of areas of high vulnerability to the socioeconomic environment after an earthquake; construction of a database of building attributes; estimation of the probability of building collapse by TELES model; assessment of road failure risk; evaluation of emergency evacuation routes based on the safety and the risk of a road failure. The procedure was applied to 5 districts of Taichung city. The analysis results indicated that the Central District and the South District of Taichung city were highly vulnerable to the road failure. Therefore, residents from these areas may have difficulty evacuating to shelters after a strong earthquake. The disaster management and evacuation plans of these areas should be reconsidered to reduce the risk of a road failure. The proposed risk analysis procedure improves risk assessment of road failure, especially in the metropolitan areas.