This paper concerned with performance analysis of single server preemptive priority retrial queue with single vacation where two types of customers are considered and they are called priority customers and ordinary customers. The priority customers do not form any queue and they have an exclusive preemptive priority to receive their services over ordinary customers. As soon as the system is empty, the server goes for vacation and the regular busy server can be subjected to breakdown. By using the supplementary variable technique, we obtain the steady state probability generating functions for the system/orbit size. Some important system performance measures and the stochastic decomposition are discussed. Finally, numerical examples are presented to visualize the effect of parameters on system performance measures. © Research India Publications.