To provide a sheet processing device capable of normally discharging sheets in a constitution in which the angle of a sheet tray can be adjusted.

It is determined whether or not there is a change of the condition of the sheet tray (step S50). In the case it is determined that there is the change of the condition, the condition of the sheet tray is confirmed (step S52). Then a job is confirmed (step S54). A discharging regulating table is referred (step S56). Then it is determined whether or not it is possible to discharge (step S58). In the case of determining that it is possible to discharge, the discharging processing is carried out by commanding the motor arranged in a saddle (step S60). On the other hand, in the case of determining that it is not possible to discharge in S58 (NO in step S58), a discharging stopping processing is carried out by commanding the motor arranged in the saddle (step S62).