A winding machine for printed substrates, comprising: a plurality of equi-rotating rollers (1, 1', 2, 2') configured to receive a leading edge of a printed substrate, for dragging it in a rolling space defined between the equi-rotating rolls (1, 1', 2, 2') and winding it on itself in the rolling space to form a roll; a support; a first guide element of the printed substrate, constrained to said support, shaped so as to define a supporting surface to support the printed substrate as it advances toward the equi-rotating rollers (1, 1', 2, 2') and a distal arched end to guide the leading edge in order to wind the printed substrate on itself; a motor unit, functionally connected to said rollers (1, 1', 2, 2') to rotate them all in a same direction; characterized in that it comprises a second guide element tied to said support, having a respective distal arched end (4'a) shaped as said first distal arched end and arranged in a mirror-like manner thereto; wherein said support is movable between a first configuration, in which the distal arched end of the first guide element is placed in said rolling space and in which the distal arched end of the second guide element is outside said rolling space, and a second configuration, wherein the distal arched end of the second guide member is located in said rolling space and wherein the distal arched end of the first guide element is outside said rolling space; an electric control (5, 5') switchable between a first state, when said support is in the first configuration, and a second state, when said support is in the second configuration, wherein said electric control (5, 5') is configured to switch said motor unit to rotate the rollers (1, 1', 2, 2') counterclockwise when in the first state and clockwise when in the second state. a plurality of equi-rotating rollers (1, 1', 2, 2') configured to receive a leading edge of a printed substrate, for dragging it in a rolling space defined between the equi-rotating rolls (1, 1', 2, 2') and winding it on itself in the rolling space to form a roll; a support; a first guide element of the printed substrate, constrained to said support, shaped so as to define a supporting surface to support the printed substrate as it advances toward the equi-rotating rollers (1, 1', 2, 2') and a distal arched end to guide the leading edge in order to wind the printed substrate on itself; a motor unit, functionally connected to said rollers (1, 1', 2, 2') to rotate them all in a same direction; characterized in that it comprises a second guide element tied to said support, having a respective distal arched end (4'a) shaped as said first distal arched end and arranged in a mirror-like manner thereto; wherein said support is movable between a first configuration, in which the distal arched end of the first guide element is placed in said rolling space and in which the distal arched end of the second guide element is outside said rolling space, and a second configuration, wherein the distal arched end of the second guide member is located in said rolling space and wherein the distal arched end of the first guide element is outside said rolling space; an electric control (5, 5') switchable between a first state, when said support is in the first configuration, and a second state, when said support is in the second configuration, wherein said electric control (5, 5') is configured to switch said motor unit to rotate the rollers (1, 1', 2, 2') counterclockwise when in the first state and clockwise when in the second state.