Phase change material microcapsules (MicroPCMs) with polystyrene as shell material and paraffin as core material were prepared by suspension polymerization. The influence of emulsifying time, the dosages of crosslinking agent (DVB), polymerization times and the mass ratios of core and shell has been studied on the properties of phase change microcapsules, such as chemical compositions, surface morphologies, thermal storage properties and stabilities of the microcapsules were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The results showed that the emulsifying time had no significant influence on the thermal properties of microcapsules. The microcapsule showed better morphology with less wrinkles and less debris when the dosage of divinybenzene(DVB) was 6∶1. The microcapsule prepared with the polymerization time of 3 h had good morphology, relatively uniform size, high latent heat of phase change and high content of core wax. As the mass ratio of the core and wall material increases, the melting temperature of the content of core material (paraffin) increases successively. When the mass ratio of the core and wall material is 3∶1, the latent heat of prepared microcapsule with good thermal stability increases to 125.2 J/g and the content of core material(paraffin) reaches up to 80.9%.