A disk drive device includes a housing having a front side with a slot through which a disk-shaped recording medium is inserted and ejected, a pickup unit including a mount on which the recording medium is mounted, a rotating mechanism that rotates the recording medium on the mount, a pickup mechanism that reproduces a signal recorded on the recording medium, a pickup-moving mechanism that moves the pickup mechanism in a radial direction of the recording medium, and a base plate that has a protruding surface guiding the recording medium toward the mount and on which the mount, the rotating mechanism, the pickup mechanism, and the pickup-moving mechanism are integrated, and a conveying mechanism that conveys the recording medium between the slot and the mount.