The work aims to improve the temperature control accuracy of heat sealing mechanism in packaging machine so as to guarantee the packing efficiency and product quality. A temperature control system for heat sealing in automatic packing machine was designed based on single neuron adaptive PID control algorithm. The basic principle of automatic packing machine heat sealing was introduced. The basic theory of single neuron adaptive PID control algorithm was expounded and a temperature controller was designed. Meanwhile the learning rate of proportion, integral and differential coefficient could be adjusted online based on the fuzzy set theory. The temperature control system for heating sealing mechanism of automatic packaging machine was constructed based on ARM Cortex-M3 and PIC. The heat sealing temperature control system was applied to automatic packing machine and its temperature error could be controlled in a reasonable range. The simulation experiment verifies that the heat sealing automatic packing machine temperature control system described in this paper has good stability as well as anti-jamming, adaptive, self-adjustment ability.