To provide a method for three-point bending test for a sheet-type test piece and an apparatus used for the same conducting a bending test with high precision and evaluating durability under rigorous bending for a sheet-type testing piece comprising a composite material including a plastic material or a plastic material like a sheet-type electrode.

The three-point bending test for a sheet-type test piece measures a bending reactive force of the sheet-type test piece by placing the sheet-type test piece on two cylindrical supports provide spaced apart by a predetermined distance, bringing a pressing rod of which the tip portion is shaped like a semicylinder into contact with the center of the sheet-type test piece, and bending the sheet-type test piece to a predetermined bending angle by gradually pressing the pressing rod thereagainst. The three-point bending test apparatus is configured such that the cylindrical supports are configured by rollers, and it includes a load sensor measuring system measuring the bending reactive force in the surface vertical direction of the sheet-type test piece. The three- point bending test for the sheet-type test piece is conducted using the test apparatus.