To improve productivity f a substrate processing device by predicting generation of abnormality before a substrate carrier mechanism fails.

When carriage of a substrate is started (N2), time counting motion of a prediction timer TF and an alarm timer TW is started (N3, N4). The prediction timer TF times up by longer prediction time than normal carrier time which a substrate carrier mechanism in a normal state requires for substrate carriage. The alarm timer TW times up by alarm time set as long as regarded as abnormality occurs in the substrate carrier mechanism. The alarm time is longer than the prediction time. When the prediction timer TF times up (N5) before substrate carrier motion is finished (N7), a counted value C of a counter is increased (N8). When this counted value C reaches a threshold value TH (N9), prediction is generated (N10) in a state where the substrate carrier mechanism is continued driving.