Three types of polymer including polyurethane, polyethylene, and polysulfone were used as filler inside composite tubes to evaluate their effects on the crashworthiness. The composite tube consisting of carbon fiber fabric and polyurethane was fabricated by resin transfer molding and subjected to impact loading. In addition, the finite element analysis with progressive failure and delamination was used to simulate the crushing behavior of the polymer-filled composite tube. From the comparison between experiment and simulation, the finite element analysis is reliable, could reasonably describe the crushing behavior of the polymer-filled tube, and has nice prediction on the crashworthiness performance. From both the experiment and simulation results, the polyethylene-filled composite tube has clearly higher specific absorbed energy than the hollow composite tube, and polyethylene could be considered as an effective filler. However, the other two types of polymer filler have no clear effect.