The invention discloses a bending and forming mechanism. The bending and forming mechanism comprises an upper mould and a lower mould; a first-time bending punch is arranged on the upper mould; a first-time bending lug boss matched with the first-time bending punch for use is arranged on the lower mould; the first-time bending punch is used for bending a metal flat plate edge placed on the first-time bending lug boss; a second-time bending punch is arranged on the upper mould; a second-time bending lug boss matched with the second-time bending punch is arranged on the lower mould; a right-angle-shaped second-time bending groove is formed in the second-time bending punch; the second-time bending groove comprises a vertical wall and a horizontal wall; the horizontal wall is positioned abovethe vertical wall; the vertical wall is used for cutting the outer side wall of the metal flat plate bending part; and the horizontal wall is used for downwards extruding the end part which is upwardsbent of the metal flat plate, so that a circular bead formed by flanging is reduced, and therefore, stress at the flanging is reduced.