Abstract: this paper examines the conversion method of the imbalanced exciting force of equipment from a bench test to a ship hull structure. A formula of the exciting force transferred to the ship structure is conducted, and a simplified method of analyzing the coupled vibration between marine equipment and the ship structure is also proposed. Based on vibration theory, the coupled vibration model of equipment and the ship structure is established by regarding equipment, the vibration isolator and installation foundation as a multi-degree-of- freedom vibration system. The exciting force transfered to the installation foundation is obtained. On that basis, a formula of the exciting force transfered to the ship hull structure is then obtained, and a simplified method for analyzing the coupled vibration between equipment and the ship hull structure is proposed and verifired. Result shows that the exciting force transferred to the ship hull structure are not only related with the equipment exciting force, but also with the mass of equipment, the stiffness and damping of isolators and the stiffness of the ship hull structure. Study also shows that the simplified method proposed has high accuracy and can meet engineering requirements.