Embodiments of present invention provide a processing method of a data packet, a terminal, a base station and a system, the terminal comprises: a receiving unit, configured to receive a first instruction sent by a first base station; a processing unit, configured to stop reordering data packets according to the first instruction received by the receiving unit, or start reordering the data packets according to the first instruction received by the receiving unit. The technical solutions provided by the embodiments of the present invention are used to achieve that an orderliness of the data packets in the terminal is guaranteed.