The invention discloses a clamping worktable for measuring an S-shaped sample, which is composed of an X-axis translation table, a Y-axis translation table and a Y-axis turntable sequentially from bottom to top, wherein the X-axis translation table, the Y-axis translation table and the Y-axis turntable are respectively provided with a first servo motor, a second servo motor and a third servo motor; upper surfaces of the X-axis translation table and the Y-axis translation table are provided with a first groove and a second groove; the first groove is internally provided with a first screw rod with a screw nut connected with the first servo motor; the second groove is internally provided with a second screw rod vertical to the first screw rod; one end of the second screw rod is connected with the second servo motor; one side of the Y-axis turntable is provided with a worm gear connected with the third servo motor; the middle of the Y-axis turntable is provided with a rotary supporting bearing engaged with the worm gear; and a clamping disc for clamping the S-shaped sample is connected onto the rotary supporting bearing. Thus, integrity of the S-shaped sample is ensured, and the measurement efficiency is greatly improved.