To improve the shape quality of the hot rolled strip, a pass schedule optimization has been developed for hot strip rolling using pair-cross (PC) mills. In this algorithm, a new flatness control criterion has been proposed, which involves the strip crown target in the classic flatness control criterion. Pass schedule is optimized to maximize the allowable control range of PC angles. Several case studies have been conducted. It has been found that the pass schedule optimization algorithm proposed by this research is very efficient. The final crown target can reach the designed crown target and the flatness can be maintained at a very small value. Through the pass schedule optimization, the PC angle control range has been enlarged. This provides operators more opportunities to adjust the strip flatness and crown.