In this study, the local stress of unidirectional fiber reinforced marine composites under transverse direction tension is conducted by using a representative volume element (RVE). With the application of fracture mechanics theory, the strength and debonding evolution of the fibre-matrix interface is analyzed and simulated by cohesive elements in FEA. The modeling results fit the experimental results in quasi-static conditions well, which demonstrates a proper simulation method for assessing the transverse mechanical properties of marine composites. Considering the complex work environment in ocean, transverse mechanical behaviors of marine composites under different strain rates is investigated, which would provide guidance for the marine composite designers.