To analyze and improve operations in food production and packaging based on ergonomics. Biomechanics of kneading and packaging in food production and packaging was analyzed by SIMMIE, the system software for aiding human-machine interaction evaluation, and the structure of work environment was improved according to the mechanical result. The force on the human body was significantly reduced after improvement, which verified the validity of this improvement. The research method based on ergonomics provided a certain basis and specifications for the design of light physical work environment.