A disk clamping mechanism comprising: a movable base unit; a spindle motor mounted on the movable base unit; a turntable fixed on a rotational shaft of the spindle motor to rotate a flexible thin optical disk; a stabilizer member arranged below the movable base unit, wherein the stabilizer member is provided with a disk placing surface adapted to support the flexible thin optical disk, the stabilizer member being configured to suppress a run-out of the flexible thin optical disk by applying an aerodynamic force to the rotating flexible thin optical disk so as to stabilize the run-out of the rotating flexible thin optical disk; and a clamper provided with a surface adapted to support and clamp the flexible thin optical disk, the clamper being movably supported in a center of the stabilizer member in a direction perpendicular to a surface of the flexible thin optical disk, wherein the flexible thin optical disk is sandwiched between the turntable and the clamper so that the turntable and the clamper rotate the flexible thin optical disk sandwiched therebetween, and wherein the disk clamping mechanism further comprises: a shaft portion provided at a lower part of the clamper to match a center of the clamper for supporting the clamper; and a supporting member configured to pivotally and rotationally support the shaft portion of the clamper, wherein the clamper that is suspended by the supporting member is attached to the stabilizer member, such that the clamper is movable from a first position to a second position relative to the stabilizer member, the stabilizer member is configured to support the flexible thin optical disk when the clamper is in the first position, and the clamper is configured to support the flexible thin optical disk when the clamper is in the second position. a movable base unit; a spindle motor mounted on the movable base unit; a turntable fixed on a rotational shaft of the spindle motor to rotate a flexible thin optical disk; a stabilizer member arranged below the movable base unit, wherein the stabilizer member is provided with a disk placing surface adapted to support the flexible thin optical disk, the stabilizer member being configured to suppress a run-out of the flexible thin optical disk by applying an aerodynamic force to the rotating flexible thin optical disk so as to stabilize the run-out of the rotating flexible thin optical disk; and a clamper provided with a surface adapted to support and clamp the flexible thin optical disk, the clamper being movably supported in a center of the stabilizer member in a direction perpendicular to a surface of the flexible thin optical disk, wherein the flexible thin optical disk is sandwiched between the turntable and the clamper so that the turntable and the clamper rotate the flexible thin optical disk sandwiched therebetween, and wherein the disk clamping mechanism further comprises: a shaft portion provided at a lower part of the clamper to match a center of the clamper for supporting the clamper; and a supporting member configured to pivotally and rotationally support the shaft portion of the clamper, wherein the clamper that is suspended by the supporting member is attached to the stabilizer member, such that the clamper is movable from a first position to a second position relative to the stabilizer member, the stabilizer member is configured to support the flexible thin optical disk when the clamper is in the first position, and the clamper is configured to support the flexible thin optical disk when the clamper is in the second position. a shaft portion provided at a lower part of the clamper to match a center of the clamper for supporting the clamper; and a supporting member configured to pivotally and rotationally support the shaft portion of the clamper, wherein the clamper that is suspended by the supporting member is attached to the stabilizer member, such that the clamper is movable from a first position to a second position relative to the stabilizer member, the stabilizer member is configured to support the flexible thin optical disk when the clamper is in the first position, and the clamper is configured to support the flexible thin optical disk when the clamper is in the second position.