A novel preheating technique to enhance laser-ablative impulse is investigated. In this technique, target material is first heated to an appropriate temperature by irradiating with a continuous laser. Impulse is generated by irradiating an intense laser pulse on the preheated material. In the experiment, polymer materials are preheated simply using an electric heater to investigate the effect of the material temperature on the laser ablative impulse. A pulsed TEA CO₂ pulse laser is used to generate impulse. The results demonstrate that the present technique is useful for Poly-vinyl Chloride (PVC), Acrylic resin (PMMA), and Carbon Fiber Reinforced Plastic (CFRP). The momentum coupling coefficient of PMMA has a peak at the temperature close to the glass transition temperature.