Abstract: To improve anti-light performance of B72, an acrylic resin and extensively used for relic protection，six different hindered amine light stabilizers (HALS) were selected to stabilize B72. From the experiment results, it had been showed that the color of B72 modified with HALS-5060 became yellow obviously in the aging process, even when HALS-5060 adding to B72，and this hindered amine light stabilizer was not suitable to modify B72. The stability of B72 modified with high molecular weight stabilizers, HALS-622 and HALS-944, was better than that of B72 modified with low molecular weight stabilizers, HALS-480, HALS-508 and HALS-292. And the performance of HALS-622 with low alkalinity was more outstanding. Therefore, the lifespan of B72 could be extended by its modification with high molecular weight and low alkaline HALS, which was a new method to conserve cultural heritage effectively.