Abstract : This article aims at assessing the internal stresses in thick laminated pipes, composed of orthotropic plies, subjected to transient thermal fields. The original contribution of the work is to provide novel analytical solutions, based on well-founded assumptions, to compute the internal stresses due to transient thermal fields throughout the pipe thickness, within the framework of thermoelasticity. The structures considered here are thick, laminated and anisotropic pipes of infinite length. They are subjected to beat flux conditions on their inner and outer surfaces due to the environmental conditions. The transient thermal field is determined and the thermoelastic stresses are derived by using the classical equations of solid mechanics and assuming a themioelastic orthotropic ply behavior. Finally, particular attention is paid to wall thickness effect.