Objective To study the process optimization and production line balancing of the electric pencil sharpener packaging line in a company. Methods Industrial engineering analysis methods were applied to improve its old packaging lines and process. According to the characteristics of the electric pencil sharpener production process, the position weighting method of production line balancing was used to rebuild a reasonable production process. At the same time, job contents, equipments, facility layouts, and operators were reassigned and adjusted. Results Compared with the original solutions, the balancing rate of the new one showed an increase of 31%, and the staff number was reduced by 4, and the order delivery rates were improved. The new layout ensured the smooth operation of the production line and met the demands of the designed output. Conclusion Using the positional weight method, combined with process optimization, decomposition and combination, better results of the production line balancing were obtained.