Two UV-curable polysiloxanes-side methacryloxy group polysiloxanes (MAPS) -were successfully synthesized through a two-step reaction. Two series of various percentages of these synthesized MAPS were then cured with bisphenol-A epoxy methacrylate (BEMA) via UV radiation to obtain cured coatings. We found that the additive MAPS improved the thermal stability of the cured coatings. It not only reduced the surface energy of the coatings, but also significantly affected the other properties, including gloss, flexibility, and water resistance. Compared to the phase separation between BEMA and MAPS-1 with lower volume of methacryloxy groups, MAPS-2 with higher volume of methacryloxy groups dispersed uniformly in BEMA, thereby provding good performances for such coating materials.