The parameter setting system according to the present invention is provided with a control panel for controlling a passenger conveyor, and a setting device for setting a control parameter relating to control of the passenger conveyor in the control panel. The control panel has a control panel storage unit. The setting device has a read function unit for reading, as control panel information, control parameter change history information stored in the control panel storage unit, and a setting device storage unit in which a past control parameter included in the control panel information is stored as a setting parameter for setting in the control panel.
