Abstract: In this paper, MX/G/1 queue with disasters and working breakdowns services is analyzed. The system consists of a main server and a substitute server. It is assumed that disasters occur only when, the main server is in operation. The occurrence of disasters forces all customers to leave the system and causes the main server to fail. At a failure instant, the main server is sent to the repair facility and the repair period begins immediately. During the repair period, the system is equipped with the substitute server which provides the working breakdown services to arriving customers. The concept of working breakdown services is included and the steady state system size distribution is derived. Various performance measures are derived and the effects of system parameters on queue length are studied.