Disclosed are a method and device for turning off and turning on a packet data convergence protocol (PDCP) packet replication function, a method and device for sending a media access control control element (MAC CE), a user equipment, a base station and a computer readable storage medium. The method for taming off a PDCP packet replication function comprises: receiving at least one MAC CE from a base station, the MAC CE carrying target carrier information; and turning off a PDCP packet replication function of a DRB or SRB that is mapped on a logical channel corresponding to a target carrier and the PDCP packet replication function of which is turned on according to the MAC CE. According to the embodiments of the present disclosure, a PDCP packet replication function of a DRB or SRB that is mapped on a logical channel corresponding to a target carrier and the PDCP packet replication function of which is turned on is turned off so as to solve the problem of a data packet on a logical channel corresponding to a deactivated target carrier not being able to be transmitted.