A disk recording/reproducing device includes a power transmitting mechanism which transmits movement of a pickup while engaging with the pickup, and a disk retaining mechanism which, in response to the movement of the pickup transmitted by the power transmitting mechanism, retains a disk on a turntable or releases retention of the disk. Radially inward movement of the pickup causes the disk retaining mechanism to retain the disk on the turntable, while radially outward movement of the pickup causes the disk retaining mechanism to release retention of the disk. For accomplishing the release of the retention of the disk upon the radially outward movement of the pickup, an operation switching mechanism is provided for changing a position of the power transmitting mechanism to cause the power transmitting mechanism to engage with the pickup upon the radially outward movement of the pickup.