The main purpose of electronic scales is to measure, which can also be said to be for trading. Electronic scales have their relevant numerical measurement value restrictions when they are used. Therefore, they can only be used effectively within the measurement value range when they are used. As long as the weight does not exceed the measurement limit, they can be used at will. This measurement method greatly improves the measurement speed and the user's trading speed. STC89C51 single chip microcomputer as an 8-bit single chip microcomputer, first of all, the price is relatively low. The number of pins of 51 single chip microcomputer is up to 40. After subtracting some power supplies and special pins, 32 pins can be used, and all 32 pins can be used as input and output pins. Therefore, the performance price ratio of 51 single chip microcomputer is relatively high. At the same time, the application circuit of 51 single chip microcomputer is relatively simple, and only the crystal oscillator circuit and reset circuit are needed to achieve work. Besides, 51 single chip microcomputer also has serial communication, timer, external interrupt and other on-chip resources, which can meet the special requirements of some systems. Finally, in terms of programming, the 51 single-chip microcomputer can be used only after loading the header file, without configuring the input and output ports, and is also very convenient in programming. Therefore, STC89C51 single chip microcomputer is used as the basis and Proteus and KILL software are used to realize the design of electronic scales.