An efficient Ru-catalyzed enantioselective hydrogenation of quinoxalinone and quinazolinone derivatives has been successfully developed, providing a straightforward and facile access to chiral dihydroquinoxalinones and dihydroquinazolinones with excellent results (89–98% yields, up to 98% ee). Importantly, the key enantiopure dihydroquinoxalinone intermediate towards the synthesis of a bioactive BRD4 inhibitor was conveniently synthesized by this catalytic hydrogenation methodology.