Injected pultrusion (IP) is an efficient process for high-quality, low-cost, high-volume manufacturing of polymeric composites with relatively simple cross sections. This process was developed recently, and efforts to develop tools for model-based design and optimization of this process have only just begun. This work focuses on developing a 3-D nonisothermal computer simulation model for the IP process. First, the governing equations for transport of mass, momentum, and energy are formulated by using a local volume-averaging approach. In turn, a computer simulation model of the IP process is developed using the finite-element/control-volume (FE/CV) approach. Specifically, the continuity equation and the conservation of momentum equation are solved rising a Galerkin FE/CV technique. The chemical species balance equation is solved in the Lagrangian frame of reference, whereas the energy equation is solved ruing the streamline upwind Petrov-Galerkin approach. Using the simulation model the effect of fiber pull speed, reinforcement anisotropy, and taper of the die on the product quality was demonstrated. In addition a simple puling-force model was developed and integrated with the simulation model. Overall, the simulation model can be effectively used to design the die geometry and to optimize the operating conditions for a given product.