Natural gas is one of the widely used sources of energy around the world. Gas transportation networks, which work at high pressure, use compressor stations to supply the needed energy to move gas between two distant sites. The present work describes a tool used to simulate the dynamic behavior of a gas compressor station. Possible transient situations can be due to the start-up or shutdown of the compressor, change of the gas flow required by the downstream gas network or switch of the station layout. The mathematical models of compressor, cooler, valve, pipe and anti-surge control are discussed. After that, the model of a one-stage gas compressor station is validated using data obtained by the Energy System Modular Solver, which was used to analyze compressor station, gas turbine and power plants in a lot of previous works. Lastly, the gas compressor station is simulated during a typical variation of the flow required by the downstream pipeline to predict its dynamic behavior.