An accelerator pedal reaction force control device for controlling a depression reaction force of an accelerator pedal provided to a motor vehicle, the control device including: a reaction force actuator that provides the accelerator pedal with a depression reaction force; a target reaction force setting unit that sets a target depression reaction force; and a vehicle speed maintenance depression amount setting unit that sets an amount of depression of the accelerator pedal for maintaining a current vehicle speed as a vehicle speed maintenance depression amount, wherein, when a pedal depression amount exceeds the vehicle speed maintenance depression amount, the target reaction force setting unit performs a cruize assist whereby the target depression reaction force is set to a value of a cruize assist depression reaction force.