In order to cut down the consumption of petroleum resources，the renewable dimer acid was used to prepare polyurethane acrylate to meet the concept of sustainable development.Three kinds of polyester diols（A-1，A-2，A-3）with different hydroxyl values were prepared through condensation of dimer fatty acid and ethylene glycol（EG）at different molar ratio，which were further reacted with toluene diisocyanate（TDI） and hydroxyethyl acrylate（HEA） to introduce acrylate groups，resulting in three photocurable polyurethane acrylate resins（B-1，B-2，B-3）. The structures of the raw materials and synthesized products were characterized by Fourier transform infrared spectroscopy（FT-IR）； Real-time infrared（RT-IR）analysis was used to study the photo-curing properties under different conditions；A universal testing machine，a differential scanning calorimeter（DSC）， and thermal gravimetric analyzer（TGA）were used to analyze and test the mechanical properties，glass transition temperatures，and thermal stability of the cured resin film，and the contact angle and pencil hardness of the coating were also tested. The results showed that as the dimer acid content increased，the viscosity and number average molecular weight of the prepared polyester diol increased，and the hydroxyl value decreased The thermalstability and adhesion properties of the final cured polyurethane acrylate resin film were almostthe same，but as the hydroxyl value content decreased，the soft segment part increased，the double bond content decreased，and the crosslink density decreased，resulting in a decrease of pencil hardness and water absorption of the cured film，and increase of the flexibility.