A panel bender (10) designed for making bends on sheet metal sheets (13) comprises a substantially C-shaped main structure (11) equipped with a fixed element (12) and a mobile element (14) designed to support and clamp in a preset position a sheet metal sheet (13) to be bent, and also comprises a substantially C-shaped blade holder structure (16) connected to the main structure (11) and mobile in space inside this by means of a series of vertical guides (15) at right angles to the plane of the sheet metal sheet (13) to be bent. The blade holder structure is equipped with an upper blade (26) and a lower blade (27) designed to enter into contact with the surface of the sheet metal sheet (13) to be bent clamped between the mobile and fixed elements (12, 14) of the main structure (11) and to deform the sheet metal sheet by means of a movement with a programmable trajectory. The blade holder structure (16) also comprises respective pairs of upper (18) and lower (18′) wedge-shaped slides connected to the vertical guides (15) and running along these, the slides (18, 18′) having counteropposing faces (30, 30′) inclined at a preset angle; each upper (18) and lower (18′) wedge-shaped slide is also connected to the main structure (11) by a respective linear actuator (32, 32′) controlled hydraulically or electro-mechanically. The movements of the linear actuators (32, 32′), which cause the movements of the wedge-shaped slides (18, 18′) in the respective vertical (Y) and horizontal (X) directions, are independent and synchronized by a numeric control system.