A bending method of bending a plate-shaped workpiece, comprising: with use of a die (10, 50) mountable on a lower table (110, 210) of a press brake (100, 200) and including a V-groove (12, 52) including a first groove wall surface and a second groove wall surface at an upper part (11, 51) thereof, and a punch mountable on an upper table of the press brake (100, 200) and including, at a workpiece pressing portion, a first surface (33, 33a, 33b, 33c), a second surface (35, 35a, 35b, 35c) and a distal end, the first surface (33, 33a, 33b, 33c) in a state of being mounted on the upper table being parallel to the first groove wall surface of the die (10, 50) in a state of being mounted on the lower table (110, 210), the distal end is provided with a tip, whose cross-sectional shape of a cross section perpendicular to the lateral direction is an arc shape, at a lower end thereof and neighboring planar portions (372, 373), and the planar portions (372, 373) are continuous to the first surface and the second surface, wherein the planar portions (372, 373) are opposed to and parallel to the first groove wall surface and the second groove wall surface in a state where the punch is advanced to the V-groove (12,52),placing the plate-shaped workpiece on the upper part (11, 51) of the die (10, 50) mounted on the lower table (110, 210) of the press brake (100, 200); pressing the plate-shaped workpiece by the workpiece pressing portion (31, 31a, 31b, 31c) of the punch mounted on the upper table of the press brake (100, 200) so as to bend the plate-shaped workpiece in a state of being sandwiched between the first groove wall surface of the V-groove (12, 52) and the first surface (33, 33a, 33b, 33c) of the punch, characterized in that an angle ( θ 2) formed between the second surface (35, 35a, 35b, 35c) and a perpendicular plane being different from an angle ( θ v/2) formed between the second groove wall surface and the perpendicular plane. with use of a die (10, 50) mountable on a lower table (110, 210) of a press brake (100, 200) and including a V-groove (12, 52) including a first groove wall surface and a second groove wall surface at an upper part (11, 51) thereof, and a punch mountable on an upper table of the press brake (100, 200) and including, at a workpiece pressing portion, a first surface (33, 33a, 33b, 33c), a second surface (35, 35a, 35b, 35c) and a distal end, the first surface (33, 33a, 33b, 33c) in a state of being mounted on the upper table being parallel to the first groove wall surface of the die (10, 50) in a state of being mounted on the lower table (110, 210), the distal end is provided with a tip, whose cross-sectional shape of a cross section perpendicular to the lateral direction is an arc shape, at a lower end thereof and neighboring planar portions (372, 373), and the planar portions (372, 373) are continuous to the first surface and the second surface, wherein the planar portions (372, 373) are opposed to and parallel to the first groove wall surface and the second groove wall surface in a state where the punch is advanced to the V-groove (12,52),placing the plate-shaped workpiece on the upper part (11, 51) of the die (10, 50) mounted on the lower table (110, 210) of the press brake (100, 200); pressing the plate-shaped workpiece by the workpiece pressing portion (31, 31a, 31b, 31c) of the punch mounted on the upper table of the press brake (100, 200) so as to bend the plate-shaped workpiece in a state of being sandwiched between the first groove wall surface of the V-groove (12, 52) and the first surface (33, 33a, 33b, 33c) of the punch, characterized in that an angle ( θ 2) formed between the second surface (35, 35a, 35b, 35c) and a perpendicular plane being different from an angle ( θ v/2) formed between the second groove wall surface and the perpendicular plane.