p53 binding protein 1(53BP1)plays a crucial role in coordinating the selection of DNA double - strand break(DSB) repair pathway. Underlying molecular mechanisms of 53BP1 recruitment to damaged chromatin and the function of histone modifications in that process have been reported in extensive literature. H4K20me2 and H2AK15ub are the key factors that determine whether 53BP1 can bind to damaged chromatin. Recent evidence suggests that the acetylation of H3K18 and H3K56,as well as the acetylation/methylation of H4K16,have a certain effect on 53BP1 recruitment. This article reviews the structure of 53BP1,the molecular mechanism of 53BP1 recruitment,and the role of histone modifications in regulating 53BP1 recruitment,and provides new ideas for cancer therapy.