Taking a typical cold rolling production system as the research background, the batch production planning problem for high-value-added O5 products is studied. Due to the extremely high surface quality requirements of these products, the associated setup costs and inventory costs in the production process are significantly high. In light of this, a mixed-integer programming model is formulated to describe the batch production planning problem for O5 products, aiming to minimize setup costs and inventory costs with full consideration of practical technological constraints. Additionally, an effective Lagrangian relaxation approach is proposed to solve the problem. A numerical experiment composed of 400 instances is designed based on actual production data. Computational results prove that high quality solutions could be found in a reasonable time.