Microcapsules containing tetradecane as the phase change material (PCM) and a shell of melamine-formalin resin were prepared by in situ polymerization. To optimize the encapsulation process, experiments were performed under various reaction conditions. Microcapsules with a high uniformity could be prepared, and the ratio of breakage of the microcapsules was less than 6% over10,000 cycles using by a circulation pump. The cooling system, which has adopted MPCM slurry as a media for transporting cold thermal energy, is designed to investigate the performance of newly developed coolant. The discharging times of cold energy in circulating 20 wt% MPCM slurry are lasted to 260 minutes as long as the sensible cooling system. Accordingly, it was demonstrated that the microcapsules prepared in the current research are suitable for potential application as heat transporting media.