Reinforced thermoplastic pipes (RTPs) represent a novel and progressive approach to pipeline construction. RTP finds several crucial applications in the oil and gas industry, especially for its non-metallic nature, which enhances its utility in corrosive environments typically found in this sector. A finite element (FE) model was generated to predict the mechanical responses of RTP under combined loadings, including critical internal pressure and pure bending load. The results of the FE model were validated through existing experimental data, and a parametric study regarding all effective parameters was carried out. The results reveal that by changing the design parameters and loading and boundary conditions, the failure mode and deformation response of RTPs will be varied. The generated design matrix was used to find the optimum design condition through multi-objective optimization methods. The proposed FE model can be used for failure prediction of RTPs with different layer configurations.