A construction machine comprising: an auto-motive vehicle body (2, 3) in a front portion side of which a working mechanism is provided; an operator's seat provided in said vehicle body (2, 3) for an operator to sit on; and a canopy provided to rise in said vehicle body (2, 3) to cover an upper side of said operator's seat, wherein said canopy comprises: a left front column provided to rise in a left front side of said operator's seat; a right front column provided to rise in a right front side of said operator's seat; a left rear column provided to rise in a left rear side of said operator's seat; a right rear column provided to rise in a right rear side of said operator's seat; a left connecting beam extending in the front-rear direction to connect said left front column and said left rear column; a right connecting beam extending in the front-rear direction to connect said right front column and said right rear column; and a roof plate provided between said left connecting beam and said right connecting beam to extend in the front-rear direction for covering the upper side of said operator's seat, characterized in that; a bend portion is provided in a front end side of said roof plate to extend in the left-right direction and project upward between a left connecting portion connecting said left front column and said left connecting beam and a right connecting portion connecting said right front column and said right connecting beam, plate-shaped lifting brackets (26, 27) are respectively provided in a position of said left connecting portion and in a position of said right connecting portion to sandwich said bend portion from both sides in the left-right direction, and a discharging notch (26B, 27B) is provided in at least one of said left lifting bracket and said right lifting bracket to a section thereof corresponding to said bend portion of said roof plate. an auto-motive vehicle body (2, 3) in a front portion side of which a working mechanism is provided; an operator's seat provided in said vehicle body (2, 3) for an operator to sit on; and a canopy provided to rise in said vehicle body (2, 3) to cover an upper side of said operator's seat, wherein said canopy comprises: a left front column provided to rise in a left front side of said operator's seat; a right front column provided to rise in a right front side of said operator's seat; a left rear column provided to rise in a left rear side of said operator's seat; a right rear column provided to rise in a right rear side of said operator's seat; a left connecting beam extending in the front-rear direction to connect said left front column and said left rear column; a right connecting beam extending in the front-rear direction to connect said right front column and said right rear column; and a roof plate provided between said left connecting beam and said right connecting beam to extend in the front-rear direction for covering the upper side of said operator's seat, characterized in that; a bend portion is provided in a front end side of said roof plate to extend in the left-right direction and project upward between a left connecting portion connecting said left front column and said left connecting beam and a right connecting portion connecting said right front column and said right connecting beam, plate-shaped lifting brackets (26, 27) are respectively provided in a position of said left connecting portion and in a position of said right connecting portion to sandwich said bend portion from both sides in the left-right direction, and a discharging notch (26B, 27B) is provided in at least one of said left lifting bracket and said right lifting bracket to a section thereof corresponding to said bend portion of said roof plate. a left front column provided to rise in a left front side of said operator's seat; a right front column provided to rise in a right front side of said operator's seat; a left rear column provided to rise in a left rear side of said operator's seat; a right rear column provided to rise in a right rear side of said operator's seat; a left connecting beam extending in the front-rear direction to connect said left front column and said left rear column; a right connecting beam extending in the front-rear direction to connect said right front column and said right rear column; and a roof plate provided between said left connecting beam and said right connecting beam to extend in the front-rear direction for covering the upper side of said operator's seat, characterized in that; a bend portion is provided in a front end side of said roof plate to extend in the left-right direction and project upward between a left connecting portion connecting said left front column and said left connecting beam and a right connecting portion connecting said right front column and said right connecting beam, plate-shaped lifting brackets (26, 27) are respectively provided in a position of said left connecting portion and in a position of said right connecting portion to sandwich said bend portion from both sides in the left-right direction, and a discharging notch (26B, 27B) is provided in at least one of said left lifting bracket and said right lifting bracket to a section thereof corresponding to said bend portion of said roof plate.