Complex queuing systems imply a discipline of services based on priority treatment of certain clients. The preemptive queuing system type is an appropriate model for numerous real systems. In [6] I have introduced the variable number of parallel working stations queuing system and in [5] I have presented a simulation algorithm for the preemptive queuing system of this type. Based on the DEVS formalism, in [4], respectively in [8], I have been proposed formal and object oriented models, for preemptive queuing system with one station, respectively with a constant number of parallel working stations. Using the same general framework, in this paper I propose a simulation model for a variable number parallel working stations preemptive queuing system. Formal and modular description of systems behavior eliminates the possibility of introducing errors. To each DEVS model, an abstract simulator we associate and using the advanced concept of Object Oriented Language C++, the abstract simulator was implemented.