A test system based on 485 network is designed and built, with the industrial control computer PC as the control unit. It implements the on-board miniaturization, intelligent unmanned, distributed networked test of metro vehicle brake disc temperature rise. Meanwhile, personal PC can receive the data collected by industrial control computer PC through the serial port. Industrial control computer PC software and personal PC software are using LABVIEW graphical language. In the case of long unattended, the industrial control computer PC automatically and completely saves vehicle brake disc temperature rise data. Personal PC, at the same time, has access to historical data saved by industrial control computer PC through the local area network. It achieves a quick copy of historical test data.