To properly determine the rolling sequence, and to enhance operation efficiency when rolling hot piece slab and/or cold piece slab in a rolling mill.

The rolling sequence of materials is determined by a data classification judgement processing partitioning the rolling sequence of the materials into only cold piece and only hot piece and the mix of the hot piece and the cold piece, by selecting a proper practice for each classification distinguished by the judgement processing, and by a processing optimizing the rolling sequence, which determines the rolling sequence by each evaluation function.