When a tensile testing machine exerts tensile force to biological tissue attached to a bone, twist and inclination of the biological tissue are so adjusted that the biological tissue and the bone can be integrally set on the tensile testing machine. A fixture 10 according to the present invention includes a holder 11, which holds a bone B, and a support 12, which supports the holder 11. The holder 11 is provided with around-bone-axis angle adjusting mechanisms 14, 15, which adjust the angle of rotation of the bone B around the bone axis of the bone B held by the holder 11. The holder 11 and the support 12 are provided with bone inclination angle adjusting mechanisms 15, 34, which adjust the inclination angle of the bone B held by the holder 11. The support 12 is provided with lateral position adjusting mechanisms 34, 35, which adjust the lateral position of the holder 11 and longitudinal position adjusting mechanisms 35, 36, which adjust the longitudinal position of the holder 11.
