As the living standards of people improve continually, commercial behavior is becoming more and more modernized, people also put forward new requirements for the speed and accuracy of goods measurement. This paper designs a weighing system of digital electronic scale which is similar to the MCU simulation, and gives the design diagram, hardware composition and software system. This system takes the 51 single chip microcomputer as the core, the main components are the dedicated 24 bits serial A/D conversion chip HX711, cantilever type resistance strain sensor, the four digital tube display. This design uses the dedicated 24 bits serial A/D conversion chip HX711, which has high resolution, simple peripheral interface, and occupies less I/O port, etc.