To provide shear deformation characteristic evaluation method and evaluation device for obtaining shear deformation evaluation characteristics having high accuracy, and a test piece for shear deformation characteristic evaluation.SOLUTION: A shear deformation characteristic evaluation method includes: forming a plane part 101, and a first constraint surface 102 and a second constraint surface 103 which are connected to each other through the plane part 101 and are inclined to the plane part 101, on a test piece 100; relatively parallel moving a first range astride the plane part 101, the first constraint surface 102 and the second constraint surface 103 and a second range astride the plane part 101, the first constraint surface 102 and the second constraint surface 103 and adjacent to the first range in a displacement direction inclined to the plane part 101, and thereby forming a wall part 106 between the first range and the second range; fluidizing a material from the second range toward the wall part 106 during parallel movement in the displacement direction in the first range and the second range and thereby shear deforming the wall part 106; and evaluating shear deformation characteristics of a shear deformation part 107 of the wall part 106.SELECTED DRAWING: Figure 4