The present invention discloses a method and apparatus for processing a data packet in a software defined network SDN protocol-based network. The method comprises: receiving a data packet forwarded by a SDN switch in the network; obtaining a rule corresponding to a data flow where the data packet is located; determining, according to the received data packet, data flow characteristics of the data flow where the data packet is located; determining timeout information of the rule according to a predetermined matching relationship between the data flow characteristics and the timeout information, the timeout information indicating time that the rule will be kept in a flow table of the SDN switch; and sending the rule and the timeout information of the rule to the SDN switch for processing the data packet by the SDN switch according to the rule. By means of the method and apparatus of the embodiments of the present invention, the timeout information of the rule may be set flexibly, so that the performance of SDN is boosted efficiently.