A monitoring system which can monitor the weighting data in the actual working conditions at real time was designed for solving the cheat with software in truck scale. The system uses an A/D weighting module for measuring weight, the hardware is based on human machine interface, and the software is designed with SCADA. The real-time data of the system is stored with SD card and transferred with 3G module. The test results show that the system is not only simple in architecture and stable in working, but also meets the design requirements and has a good application prospect.