Microencapsulated phase change material (MEPCM) with dodecanol as the core material and urea-formaldehyde resin as the wall material was prepared using an in situ polymerization approach in this work. The effects of the ratio of core to wall material (0.5-1.5), the content of OP-100 (0.1-0.3 wt%), and the content of resorcin (1-3 wt%) on the mass content of dodecanol in the final product were evaluated by a complete 23 central composite rotatable design. The products obtained were characterized using a scanning electronic microscope (SEM), differential scanning calorimeter (DSC), and thermogravimetric analyzer (TGA). The MEPCMs obtained were spherical microparticles with a rough surface and an average diameter of about 1 mu m. The content of dodecanol in the MEPCMs obtained is up to 64.7 wt%. The results from the TGA show that the microcapsules prepared have excellent thermal stability with a two-stage decomposition profile at considerably high temperatures (above 80 degrees C). Finally, the optimum conditions were a ratio of core to wall material 1.5, the content of OP-100 0.24 wt%, and the content of resorcin 2 wt%.