A packet processing method and an apparatus, where the method includes determining a to-be-installed flow entry and packet sending information, and sending, to a switch, a flow entry installation message carrying the to-be-installed flow entry and the packet sending information, such that the switch obtains the to-be-installed flow entry and the packet sending information from the flow entry installation message, installs the flow entry, and sends a packet according to the packet sending information. In the present disclosure, a controller sends a flow entry installation message carrying a to-be-installed flow entry and a packet sending message, where the to-be-installed flow entry and a to-be-sent packet are simultaneously sent, such that a switch simultaneously receives the to-be-installed flow entry and the to-be-sent packet, and performs flow entry installation and packet sending.