This paper deals with a method for static and dynamic modeling of a three-way pneumatic proportional valve actuated by means of a proportional solenoid, which can be applied in robust design, condition monitoring, and development of advanced control strategies. Test-beds for the experimental identification of the main physical parameters of the valve are described along with the proposed experimental methods. A mechatronic dynamic model of the valve is then presented, which considers the servo-solenoid as the electromagnetic subsystem, the moving parts of the valve as the mechanical subsystem, and the fluid parts for flow-rate control as the pneumatic subsystem. Finally, the proposed mechatronic dynamic model is validated by comparing the experimental and simulated diagrams for adsorbed current, spool position, and instantaneous flow-rate.