To prevent a defective part from being formed due to the deterioration of substrate processing accuracy when a line is automatically restarted after a stop regarding an operation control method of the substrate processor that performs continuous processing by being included in a substrate processing line or a liquid crystal panel production line of a chamfering machine or other substrate processors which shape and process cut edges of glass substrates.

When the line automatically stops due to congestion, a stop period is measured. When operation is automatically restarted after the automatic stop, the measured period is determined whether it exceeds a permissible stop period or not. When the measured period does not exceed the permissible stop period, operation is started without warmup operation, however when it exceeds the permissible stop period, the warmup operation is performed for a predetermined period or at a predetermined frequency and operation is restarted after registering a new correction value with a command value of a processing dimension registered in a controller.