Abstract: According to existing the issues,such as the current network technology updates quickly,laboratory equipment is difficult to meet the teaching requirements and so on,one puts forward an idea that use the network simulator to assist in vocational and technical schools network major practice teaching.This paper describes the functions and features of three kinds of Cisco networking equipment simulator.Especialy,this paper introduces the functions and features of Packet Tracer simulator in order to properly choose simulator and effectively improve teaching effect.