A binding machine, comprising: a staple accommodating portion including a base end portion and a front end portion on an opposite side of the staple accommodating portion from the base end portion, the staple accommodating portion being configured to accommodate a U-shaped staple including a crown portion and a pair of leg portions (101, 102) at least at the front end portion with the crown portion facing downward; a staple driver located below the front end portion of the staple accommodating portion, movable relative to the staple accommodating portion from below to above in the staple accommodating portion, and configured to push the staple located at the front end portion upward while pushing the crown portion of the staple; and a clincher provided at a position above the front end portion of the staple accommodating portion and facing the staple driver, and configured to be abutted against the pair of leg portions (101, 102) of the staple pushed out in a process of the staple driver moving upward from below so as to fold the pair of leg portions; characterized in that the binding machine further comprises a staple guide portion adjacent to the staple in the staple accommodating portion and configured to support the crown portion of the staple from a side near the base end portion of the crown portion in a process of the staple being pushed out; and a clincher guide located at the front end portion of the staple accommodating portion and forming a front wall surface of the staple accommodating portion, wherein the staple guide portion is attached to the clincher guide to be fixed in position with respect to the front wall surface formed by the clincher guide, and has an extending portion that extends to an inside of the staple accommodating portion and a through hole into which the front end portion of the staple accommodating portion is inserted. a staple accommodating portion including a base end portion and a front end portion on an opposite side of the staple accommodating portion from the base end portion, the staple accommodating portion being configured to accommodate a U-shaped staple including a crown portion and a pair of leg portions (101, 102) at least at the front end portion with the crown portion facing downward; a staple driver located below the front end portion of the staple accommodating portion, movable relative to the staple accommodating portion from below to above in the staple accommodating portion, and configured to push the staple located at the front end portion upward while pushing the crown portion of the staple; and a clincher provided at a position above the front end portion of the staple accommodating portion and facing the staple driver, and configured to be abutted against the pair of leg portions (101, 102) of the staple pushed out in a process of the staple driver moving upward from below so as to fold the pair of leg portions; characterized in that the binding machine further comprises a staple guide portion adjacent to the staple in the staple accommodating portion and configured to support the crown portion of the staple from a side near the base end portion of the crown portion in a process of the staple being pushed out; and a clincher guide located at the front end portion of the staple accommodating portion and forming a front wall surface of the staple accommodating portion, wherein the staple guide portion is attached to the clincher guide to be fixed in position with respect to the front wall surface formed by the clincher guide, and has an extending portion that extends to an inside of the staple accommodating portion and a through hole into which the front end portion of the staple accommodating portion is inserted.