A method for moving between communications systems and an apparatus, where the method includes: receiving, by a user equipment (UE), a first message, where the first message is used to set up or modify a first evolved packet system (EPS) bearer for the UE in the first communications system, and the first message includes first quality of service (QoS) flow information that is of the second communications system and corresponds to the first EPS bearer; storing, by the UE, the first QoS flow information; moving, by the UE, from the first communications system to the second communications system; and determining, by the UE based on a first condition, QoS flow information used by the UE in the second communications system, where the first condition includes the first QoS flow information.