An upper tool for (9) a press brake, removably attached on an upper tool holding device (1) mounted on an upper table (3) of the press brake, comprises: a wedge portion (9W) having a contact surface (9F) brought into contact with a lower surface of a support plate (7) provided on a holder body (5) of the upper tool holding device, a slide surface (9S) slidably brought into contact with any of front and rear surfaces of the support plate (7), and a clamp surface (9C) brought into pressure contact with a pressing-down and fixing section of an upper-tool pressing-down and fixing member (11) of the upper tool holding device; and a work processing portion (9M) for processing a workpiece in cooperation with a lower tool (59). Further, an upper tool holding device (1) for a press brake, for removably mounting and supporting an upper tool (9) on an upper table of the press brake, comprises: a holder body (5) attached to the upper table (3); a support plate (7) provided on a lower portion of the holder body; an upper-tool pressing-down and fixing member (11) attached to the holder body, for fixedly fastening an upper portion of an upper tool (9) in cooperation with the support plate (7); a clamp force adjusting device (13) for adjusting clamping force of the upper-tool pressing-down and fixing member; and a clamp releasing device (15) for releasing the clamped upper tool.