Objective To improve the bottleneck process of a horizontal coil packaging line in a company, and to solve the situation that the balancing rate of the steel coil packaging production line is too low. Methods The MOD method of Predetermined Time Standard was used, with ECRS and the economics of motion as guide the principle, and with the help of a production line balance theory. Results The improved scheme increased the balancing rate of the production line, reduced the production tempo, and improved the efficiency of the packaging. Conclusion Using the MOD method, the production line balance rate was increased from 52. 98% to 67. 40% .