The work aims to design an efficient and stable egg grading and packaging production line to improve the efficiency and quality of fresh egg processing by extension machine in China. According to the specific requirements of graded processing and packaging of eggs and based on the transmission principle of CAM gear and other mechanical structures, an egg grading and packaging production line was designed. The egg grading and packaging production line was actuated by a 1 000 W motor and was driven by chains and gears to realize the procedures of weighing, grading and loading of eggs. After processing according to the design, the prototype was installed and the experiment was carried out. It was found that the correct grading rate of the measurement error of the egg grading and packaging system was 97%, and 3 eggs were damaged after 20 repeated experiments on 100 eggs, with a low breakage rate. The highest productivity was 35 000 eggs per hour after testing. The egg grading and packaging system designed meets the design requirements, meets the market demand, and provides a technical solution for graded processing of eggs in China.