The invention relates to a rivet nut (10) with a base part (12) and a cylindrical rivet section (14), the base part having a central threaded cylinder (16), an annular contact surface (18) that is coaxial to the threaded cylinder in a plane (20) perpendicular to the longitudinal axis (22) of the threaded cylinder, and that has an axially aligned annular groove (24), said groove being arranged radially inside the annular contact surface and radially outside the cylindrical rivet section and said groove blending, on the radially inner side, into the outer surface of the cylindrical rivet section, and antirotation ribs (42) being provided in the area of the annular groove. The invention is characterized in that the annular groove, when seen in an axial cross-sectional plane, has a U-shaped cross-section with a radially outer lateral wall (30) which is relatively steep and which has, at the steepest point (33), an inclination to the center longitudinal axis of the rivet nut in the range of approximately 45° to approximately −20°, preferably of approximately 30° to approximately 0°. The volume of the annular groove is chosen in such a manner that across a range of sheet thicknesses adapted to the respective thread size there is room for the volume of the respective folded region of the rivet section inside the annular recess (80) that is formed by molding the sheet part (60) into the annular groove of the element and that it does not project beyond the side (82) of the molded sheet facing away from the annular contact surface.