PURPOSE: To enable accurate determination of a tensile characteristic of a brittle material, by producing a powder cushion from a boron nitride powder with the average particle size of below 200μm with 1.1W3.0g set for the filling into the receiving member.

CONSTITUTION: As a cross head is lowered with the action of a driving means, a tensile load is transmitted to a test piece 2 through a link member 7, a sup port shaft 6, a holder 4, a cap member 5, and a receiving member 1. At this point, when a misalignment of the test piece 2 takes place, a powder cushion 3 which is produced from boron nitride with the average particle size of below 200μm with 1.1W3.0g set for the filling into the receiving member 1 fluidizes within such a range as to eliminate possible eccentric load and coagulates in place under the subsequent tensile load to absorb the misalignment of the test piece 2. This can suppress the generation of a bending stress at the parallel part of the test piece 2 thereby enabling accurate determination of a tensile characteristic of a brittle material such as ceramics.