In recent years, with the impact of human activities on the natural environment and the periodic change of global climate, the number of extreme natural disasters such as typhoons, ice and snow, and earthquakes has been increasing. This study introduces a fault rate assessment model of distribution network lines based on equipment health under wind and rain disasters, which includes the following steps: First, the stress of distribution network wires and pylons under typhoon and rainstorm is analyzed, and the failure rate model of wires under typhoon rainstorm disaster is obtained based on the pressure of wires. Then, the failure rate evaluation model of the distribution network line with equipment health is obtained by combining the failure rate model of typhoon, rainstorm, and equipment health. Finally, a case is given to verify the effectiveness of the proposed model.