Abstract: Poly (β-amino ester)s (PβAEs) contain tertiary amine backbones and biodegradable ester bonds, making them highly biocompatible and pH-responsive. Meanwhile, originated from combinatorial libraries, PβAEs are simple to synthesize, easy to obtain raw materials and can be easily adapted to meet the different performance needs of gene carriers by adjusting the monomer type, monomer ratio and reaction time. Therefore, PβAEs are promising material for non-viral gene carriers. This paper provides a comprehensive overview of the properties and synthesis of PβAEs gene carriers and summarizes the progress of research on the gene delivery of each type of PβAEs.