At present, there is an increasing emphasis on planning production and assembly systems. In the planning phase, it is important to eliminate as much as possible, ideally all deficiencies and errors of the intended system. Simulation software helps to find shortcomings in production or assembly systems. Using simulation, we can analyze individual parts of production systems in a virtual environment before they are implemented. This all leads to cost savings in the implementation of production systems. The article deals with simulation of production systems and their planning. The case study will illustrate the simulation process in choosing the right manufacturing system.