［Objective］In order to reduce the curing temperature of polyimide（PI）system and to ensure its reaction controllability and storage stability.［Methods］This study synthesized a biomass-derived thymine-based photobase generator，thymine-1-acetic acid diazabicyclononene salt（TY-DBN），and applied it to cure polyamic acid resin coatings.［Results］TY-DBN released the superbase 1，5-diazabicyclo［4. 3. 0］-5-nonene（DBN）under UV irradiation. The curing kinetics demonstratedthat the optimal curing temperature decreased from 197. 00 ℃ to 60. 11 ℃，the apparent activation energy was reduced by two orders of magnitude（from 4. 49×10⁴ J/mol to 6. 57×10² J/mol）， and the reaction order decreased from 0. 93 to 0. 28. Normalized infrared spectroscopy confirmed a significantincrease in the imidization degree of the coating resin after low-temperature curing.［Conclusion］This study significantly improved the thermal curing performance of polyamic acid resin，providing a research strategy for developing low-temperature curable polyimide coating.