To realize high throughput by a method wherein occurrence of a play in a plurality of aligned processors is reduced extremely.

A single processor group is constituted by aligning a plurality of processors 3 having each fixed process condition, and a storing rack 2 for accommodating a plurality of works having a different process condition is installed at one end of this processor group, and these works are conveyed to the processor 3 having the corresponding process condition, and a desired process is executed. A process time of each processor 3 is set so that, as moving farther from the storing rack 2, a process time is reduced, and initially the work using the processor 3 disposed farthest from the storing rack 2 out of works accommodated in the storing rack 2 is conveyed to the corresponding processor 3, and thereafter the works using the processor 3 closer to the storing rack 2 than the work conveyed previously are sequently conveyed to the corresponding processor 3. A carrier L1 is in the middle of being conveyed from a preliminary position P2 to a process preparing position P3, and a carrier L2 stands by at the preliminary position P2, and further a carrier L3 is being prepared for conveyance at a carrier mounting position P1. When an operator found out inconveniences in the carrier L3, he continues to push an input confirmation buttom for 3 to 10 sec. In the carrier L3 which has not yet been input for confirmation, a master controller set it as a process releasing state. Further, when an operator found out inconveniences in the carriers L1, L2, he continues to push an input confirmation buttom for 10 sec. or more. The master controller set the carrier L3 as a process releasing state, and also conveys the carriers L1, L2 toward the carrier mounting position P1 by a substrate conveying robot.