In order to solve the problem of environment adaptability of Ethernet switch in artillery integrated electronic system and meet the requirements of domestic design, designing a Gigabit 2-layer network switch based on domestic ARM architecture microcontroller chip GD32F407 and domestic switch chip JEM5396A. Complete the thermal design of the switch through Flotherm software and verify the rationality of the design by simulation; produce a physical prototype, write driver software and complete debugging, high temperature work test and performance test. The test results show that the switch can work normally under high temperature conditions, meet the design index, and meet the requirements of localization and independent control.