Network polyurethane shell microencapsulated phase change materials (MicroPCMs) was successfully prepared by interfacial polymerization method using isophorone diisocyanate (IPDI) and triethanolamine (TEA) as monomers. The effect of different core/wall ratio on the surface morphology and particle size distribution of microcapsules was investigated, and the effect of TEA dosage on the surface morphology, chemical structure, thermal stability and compactness of microcapsules was also investigated. The results show that the prepared microcapsules were spherical with smooth and contact surface, and the surface cave of microcapsules disappeared when the core/wall ratio was greater than 3:1. When the core/wall ratio was 3:1 and the TEA dosage was 3.5g，the MicroPCMs has good thermal stability and compactness which can withstand high temperature of 200℃, and the mass loss rate was less than 6.2%wt after drying at 120℃ for 6h. The MicroPCMs have obviously thermal energy storage performance, and the melting temperature and melting enthalpy were 22.5℃ and 86.37J?g-1 respectively.