A method for setting software defined network (SDN) flow entries. A packet transmitted from a host is received, and a local flow table of the SDN switch for a flow entry that matches address information of the packet is searched. In response to determining that the packet matches a default flow entry in the local flow table, the packet is transmitted to a SDN controller according to the default flow entry. A first flow entry in the local flow table is set according to a source address, a destination address and an input port of the packet. A priority of the first flow entry is higher than a priority of the default flow entry. An action of the first flow entry is a non-forwarding action.