The purpose of the work is to numerically simulate and mathematically describe an experimental model of a mechatronic analogy of a human circulation system. The examined laboratory system consists of pneumatic elements to model the blood circulation system. Two containers with rubber membranes model heart ventricles, another four similar containers model the capacity and elasticity of arteries and veins. Two pneumatic valves are used to control the pressure in main chambers. To analyze the dynamics of the system, four digital pressure sensors are used to measure the system pressures. The step and ascending linear input signal responses were examined.