A sheet stacking device includes sheet stacking portion, electric motor, current detecting portion, abnormality determining portion, and updating portion. The sheet stacking portion is supported to be movable in up-down direction and configured to stack sheets thereon. The electric motor outputs, to the sheet stacking portion, a driving force for moving the sheet stacking portion in up-down direction. The current detecting portion detects a current value of the electric motor. The abnormality determining portion determines that the sheet stacking portion is in abnormal state when the detected current value is greater than a predetermined threshold. The updating portion updates the threshold based on the current value that was detected by the current detecting portion while the sheet stacking portion with a predetermined set amount of sheets stacked thereon was being moved by the driving force received from the electric motor.