Tanker trucks carrying flammable and explosive materials on highways pose risks to infrastructure, including bridges, particularly concerning parallel steel wire cables used in cable-supported bridges. To investigate the dynamic response of these cables under combined fire and explosion effects and assess their safety, a numerical simulation study was performed. The simulation’s accuracy was validated by comparing it with existing cable explosion tests. The temperature-time history of the cable was acquired after the heat transfer analysis. With a simplified constitutive model considering high-temperature and high-strain rate effects, simulations for the cable under explosions at different maximum temperatures were conducted. Finally, a damage calculation method based on critical fracture strain and effective plastic strain was developed for safety assessment. Results indicate that during a tanker truck fire, steel wire heating accelerates initially but slows near maximum temperature. High-temperature softening affects the cable's response during explosions. As temperature rises, the maximum cable force decreases, and the effective plastic strain increases. When maximum temperatures exceed 400 ℃, transverse displacement of the cable is apparently affected and the frequency decreases. The proposed damage calculation method effectively reflects damage, making the safety assessment process reasonable and effective.