A route searching method for a packet forwarding device, comprising: receiving, by an allocation node of the packet forwarding device, a destination internet protocol, IP, address of a packet sent by an ingress node of the packet forwarding device, wherein the allocation node stores an allocation table, an allocation table entry of the allocation table comprises a match item field and a searching node number field, the match item field is a prefix corresponding to a root node of a prefix subtree, and the searching node number field is a physical box number of a searching node on which routing information of the prefix subtree is located; performing, by the allocation node, matching of the match item field in the allocation table according to the destination IP address in a longest prefix match, LPM, principle, wherein the LPM principle is an algorithm that is in an IP protocol and that is used by a router to perform selection in a routing table; if the destination IP address successfully matches a first match item field in the allocation table, obtaining, by the allocation node, a physical box number of a first searching node on which routing information of a first prefix subtree corresponding to the first match item field is located, wherein the first searching node is one of a plurality of searching nodes of the packet forwarding device; and sending, by the allocation node, the destination IP address to the first searching node, wherein the first searching node stores a routing table, a routing table entry of the routing table comprises a prefix field and an egress port field, the prefix field is a proper prefix in the first prefix subtree, the egress port field is a physical box number of an egress node and an egress port number, and the egress node is an egress node of the packet forwarding device. receiving, by an allocation node of the packet forwarding device, a destination internet protocol, IP, address of a packet sent by an ingress node of the packet forwarding device, wherein the allocation node stores an allocation table, an allocation table entry of the allocation table comprises a match item field and a searching node number field, the match item field is a prefix corresponding to a root node of a prefix subtree, and the searching node number field is a physical box number of a searching node on which routing information of the prefix subtree is located; performing, by the allocation node, matching of the match item field in the allocation table according to the destination IP address in a longest prefix match, LPM, principle, wherein the LPM principle is an algorithm that is in an IP protocol and that is used by a router to perform selection in a routing table; if the destination IP address successfully matches a first match item field in the allocation table, obtaining, by the allocation node, a physical box number of a first searching node on which routing information of a first prefix subtree corresponding to the first match item field is located, wherein the first searching node is one of a plurality of searching nodes of the packet forwarding device; and sending, by the allocation node, the destination IP address to the first searching node, wherein the first searching node stores a routing table, a routing table entry of the routing table comprises a prefix field and an egress port field, the prefix field is a proper prefix in the first prefix subtree, the egress port field is a physical box number of an egress node and an egress port number, and the egress node is an egress node of the packet forwarding device.