A method for a mobile terminal to access the network through a cell phone, comprising the steps of: A. pre-establishing a connection management Hash table used for tagging a network address mapping relationship in a network enabled cell phone, wherein a Hash value in the connection management Hash table is equal to a modulus table length of a binary sum of a source address, a protocol type, a source port and a destination port; B. establishing, by a mobile terminal, a point-to-point communication connection with the network enabled cell phone through WIFI, and sending a data packet of a destination server to the network enabled cell phone; C. extracting, by the network enabled cell phone, an element group in the data packet sent by the mobile terminal at a network layer and saving the element group in a tuple structure, wherein the element group comprises a source address, a source port, a protocol type, a destination address and a destination port of the data packet; D. carrying out, by the network enabled cell phone, NAT treatment on the element group, translating the source address of the data packet to an IP address for the dial-up networking of the cell phone, and distributing a dial-up networking port; and E. connecting the network enabled cell phone to the destination server to communicate according to information of the treated element group; wherein between the step C and the step D, further comprising the steps of: - searching, by the network enabled cell phone, the connection management Hash table according to the element group, wherein searching the hash table is a hash-based lookup, - determining whether a connection structure of the mobile terminal and the destination server exists in the connection management Hash table, - defining the data packet as the first data packet and - establishing a new connection structure in the Hash table if the connection structure does not exist in the connection management Hash table. A. pre-establishing a connection management Hash table used for tagging a network address mapping relationship in a network enabled cell phone, wherein a Hash value in the connection management Hash table is equal to a modulus table length of a binary sum of a source address, a protocol type, a source port and a destination port; B. establishing, by a mobile terminal, a point-to-point communication connection with the network enabled cell phone through WIFI, and sending a data packet of a destination server to the network enabled cell phone; C. extracting, by the network enabled cell phone, an element group in the data packet sent by the mobile terminal at a network layer and saving the element group in a tuple structure, wherein the element group comprises a source address, a source port, a protocol type, a destination address and a destination port of the data packet; D. carrying out, by the network enabled cell phone, NAT treatment on the element group, translating the source address of the data packet to an IP address for the dial-up networking of the cell phone, and distributing a dial-up networking port; and E. connecting the network enabled cell phone to the destination server to communicate according to information of the treated element group; - searching, by the network enabled cell phone, the connection management Hash table according to the element group, wherein searching the hash table is a hash-based lookup, - determining whether a connection structure of the mobile terminal and the destination server exists in the connection management Hash table, - defining the data packet as the first data packet and - establishing a new connection structure in the Hash table if the connection structure does not exist in the connection management Hash table.