A series of acrylic oligomer which can undergo self-initiation under UV irradiation were synthesized by Michael addition of acetylacetone (acac) with multi-functional acrylates using diazabicycloundecene as catalyst. GC-MS and proton NMR were employed to study the photolysis mechanism of model molecule which was prepared from acac and ethyl acrylate. The beta-diketone moiety attached to a fully substituted carbon atom was photoscissile and prone to produce alkyl free radicals by losing acetyl free radical. Polymerization of the acrylated beta-diketone-containing oligomers can be thus efficiently triggered regardless of solely irradiated under UV light or blended with pure trimethylolpropane triacrylate. As determined with photo-DSC, the acrylated beta-diketone-containing oligomers photo-polymerized more slowly than the traditional system of trimethylolpropane triacrylate containing Darocur 1173 at the early stage, but reached a higher final conversion. The rheology measurement showed that the synthesized acrylated beta-diketone-containing oligomers exhibited shear thinning property.