A Network Address Translation (NAT) method, apparatus and device are provided. Based on the method, a target IP address and its reference port are obtained from a NAT resource pool, wherein the reference port is a port in a consecutive port range of the target IP address; a first five-tuple corresponding to a packet is generated based on the target IP address, the reference port and an original five-tuple of the packet, and a second five-tuple is obtained by masking first-class bits of two classes of ports of the first five-tuple respectively; a target five-tuple is determined in a plurality of consecutive hash buckets of a hash table based on a hash result of the second five-tuple; and the target five-tuple and the original five-tuple are recorded in the hash table and a corresponding result table, and the packet is NAT-processed based on the target five-tuple.