An occupant protection device includes a seat belt that restrains an occupant, an adjusting device that relatively adjusts a positional relationship between the seat belt and the occupant, a collision predicting portion that predicts a collision, and a control portion that controls the adjusting device when the collision is predicted by the collision predicting portion. The control portion first operates the adjusting device at a first speed to restrain the occupant by the seat belt, and then operates the adjusting device to increase the distance between the seat belt and the occupant at a second speed that is slower than the first speed.