The invention discloses a network simulation method and system, and relates to the field of network simulation. The method comprises the following steps of: a simulation starting process: after creating a virtual process and a virtual interface thereof, configuring the virtual process according to a preset configuration file; a data packet communication process: after the virtual process receivesthe data packet, forming the data packet into an Ethernet packet, if the communication mode of the virtual interface of the current virtual process is a virtual communication mode, packaging the Ethernet packet, and sending the Ethernet packet to a target virtual process; and if the communication mode of the virtual interface of the current virtual process is a real communication mode, directly sending the Ethernet packet to a target real device. When network simulation is carried out, the operation process can be simplified while the operation expenditure of the system is reduced, and peoplecan use the system conveniently.