This drive control device (10) is installed on a vehicle, and controls the drive of the present vehicle on the basis of a predicted course which is the prospective drive course of the present vehicle. The drive control device (10) comprises: a preceding vehicle position storage unit (25a) that chronologically stores preceding vehicle positions which are positions of a preceding vehicle driving ahead of the present vehicle; a predicted course calculation unit (21) that calculates a predicted course on the basis of the trajectory of the preceding vehicle positions; and a nullification determination unit (27) that nullifies the preceding vehicle positions stored in the preceding vehicle position storage unit (25a) in cases where it is determined that either the present vehicle or the preceding vehicle is in a situation where it is estimated that either one will deviate from the drive course.