A disk loading/ejection mechanism in a disk device inserting and taking out a disk-shaped storage medium (disk D) through an opening and enabling a combined relatively large space to be secured inside the disk device, provided with an offset drive function unit for shifting the loading/ejection direction when inserting and taking out the disk D to a loading/ejection direction (B) offset from the straight direction (A) perpendicularly intersecting the opening direction of the opening.