For the effective utilization of unused thermal energy, the novel adsorption heat pump system for generating high-temperature steam is proposed. This system adopts a direct heat exchange method to the adsorption heat pump to increase heat transfer rate between adsorbent and heat transfer fluid. The heat pump system consists of two processes: steam generation process and regeneration process. In the steam generation process, water is directly introduced to the adsorbent. In the regeneration process, dry gas is introduced to the adsorbent. In this study, the performance of the system is numerically evaluated. The efficiency of the heat pump system is calculated by the ratio of enthalpy of product steam to input energy. To calculate the enthalpy of steam, mass of steam generated is estimated based on the progress of the regeneration process. Input energy of the heat pump system consists of the blower power to introduce dry gas and the thermal energy to heat dry gas. The effect of the operating condition on the performance of the steam generation process is studied. It is found there is the appropriate regeneration time to maximize the efficiency of the heat pump system.