The work aims to precisely control the temperature of the heat-sealing device of the heat-sealing machine used for sealing the plastic film bags in fuzzy adaptive PID control method, so as to improve the sealing quality of heat-sealing device for packaging machines. With respect to the control of heat-sealing temperature of packaging plastic film, a type of automatic heat-sealing temperature control system was designed based on fuzzy adaptive PID control algorithm. The self-tuning of control parameters and the self-adjusting of control rules were realized by using variable universe fuzzy PID. The control results were compared with those of traditional PID. The fuzzy PID control method could control the heating temperature in a more stable way than the traditional PID control and it improved effectively the response speed and precision of temperature control. The system can accurately and quickly control the heat-sealing temperature, and it has the application value.