In this paper a parametric design procedure of electrical machines used in naval propulsion systems is developed. The algorithm uses a series of design characteristics i.e. the type of the machine, the winding configuration and key geometrical properties, as parameters and is implemented on MATLAB® script allowing for a straightforward incorporation with other development tools. Using the proposed algorithm, two of the most common machine configurations involved in marine electrical propulsion systems i.e. the Induction Motor and the Synchronous Permanent Magnet Motor, are designed and 2D finite element modeling and analysis is performed. MATLAB® is used to interact with the FEMM software package through ActiveX framework, allowing for a detailed calculation of the electromagnetic properties of the machines examined.