To provide an axial deviation adjusting structure in a load test, in which the axial center of specimen can be made to agree precisely with the axial center of a fitting member without applying an initial strain to the specimen, in which the deviation of the axial center is not generated during the test, and in which a test load can be transmitted precisely to the specimen.

In a testing apparatus, a specimen and a fitting member 2 which is fitted to it are connected by a fitting part 1a and a fitting part 2a, and the strength of the fitting part of the specimen 1 is tested. The testing apparatus is provided with a deviation preventive device 10 which prevents the deviation of the axial center of the fitting part. A deviation preventive device 10 is composed of a body 12 which is attached to the fitting member 2 so as to be freely detachable, of a pressure member 14 by which the fitting part of the specimen is sandwiched and held in a direction at right angles to a test load and of a position adjusting implement 16 (an adjusting bolt) which moves the pressure member 14 to a direction at right angles to the test load. A rigid plate is moved and held in a direction at right angles to the test load by using the tip part of the adjusting bolt.