In this paper, we propose an approach for integrated process planning and scheduling through analysis of the alternative operations sequences and machine selection in supply chain with multiple plants. It takes into account such factors alternative machine, alternative operations sequences, setup time, transportation time between plants, along with other manufacturing factors. The objective of the model is to minimize makespan of machine schedules for all parts, determines operations sequence for each part, and selects a machine for each operation simultaneously. Examples are presented to demonstrate the effectiveness of the proposed approach.