The occurrence of a vehicle collision is determined using an output signal of one satellite sensor disposed offset from a vehicle center line. A control device for an occupant protection device includes an acceleration sensor disposed at a front position of a vehicle; and a control unit that determines the occurrence of a collision based on an output signal of the acceleration sensor and operates an occupant protection device. The acceleration sensor is one satellite sensor disposed so as to be offset in a vehicle width direction from a vehicle front center position. The control unit includes: a first threshold setting unit that sets one or more thresholds so as to correspond to a traveling speed of the vehicle or a relative speed signal related to the relative speed between a vehicle and another movable objects such as another vehicle; and a determining unit that compares a level of the output signal of the acceleration sensor with the one or more thresholds to determine the occurrence of a collision.