A cleaning device for use with an image forming apparatus, said cleaning device comprising; a frame; a cleaning member, mounted to said frame, for removing a developer from a surface of an image bearing member, said cleaning member including a blade member contactable to the surface of the image bearing member and a supporting member supporting said blade member, said supporting member including a first flat surface (6b2), a second flat surface (6b3) extending in a direction crossing with said first surface (6b2), and a bent portion (6b1) connecting said first surface (6b2) and said second surface (6b3) over an entire longitudinal area of said supporting member, said blade member extending along the longitudinal direction of the supporting member at an end portion of the first surface (6b2) opposite from said bent portion (6b1) with respect to a direction crossing with the longitudinal direction; and a sealing member of sealing resin material provided between said cleaning member and said frame, said sealing member including a first seal portion formed so as to contact said blade member and the first surface (6b2) and to seal between said cleaning member and said frame at each of one and the other longitudinal end portions of said cleaning member, characterized in that a second seal portion is formed so as to seal between said supporting member and said frame in a region between the first seal portion at the one end portion and first seal portion at the other end portion along the longitudinal direction, wherein said sealing member is formed so as to tilt the line coinciding with the center of said second seal portion to said supporting member at an angle θ, and said second seal portion is contacted to said supporting member in a cross section perpendicular to the longitudinal direction of the supporting member, wherein said angle θ between said second seal portion and said supporting member satisfies 0°<θ<90°. a frame; a cleaning member, mounted to said frame, for removing a developer from a surface of an image bearing member, said cleaning member including a blade member contactable to the surface of the image bearing member and a supporting member supporting said blade member, said supporting member including a first flat surface (6b2), a second flat surface (6b3) extending in a direction crossing with said first surface (6b2), and a bent portion (6b1) connecting said first surface (6b2) and said second surface (6b3) over an entire longitudinal area of said supporting member, said blade member extending along the longitudinal direction of the supporting member at an end portion of the first surface (6b2) opposite from said bent portion (6b1) with respect to a direction crossing with the longitudinal direction; and a sealing member of sealing resin material provided between said cleaning member and said frame, said sealing member including a first seal portion formed so as to contact said blade member and the first surface (6b2) and to seal between said cleaning member and said frame at each of one and the other longitudinal end portions of said cleaning member, characterized in that a second seal portion is formed so as to seal between said supporting member and said frame in a region between the first seal portion at the one end portion and first seal portion at the other end portion along the longitudinal direction, wherein said sealing member is formed so as to tilt the line coinciding with the center of said second seal portion to said supporting member at an angle θ, and said second seal portion is contacted to said supporting member in a cross section perpendicular to the longitudinal direction of the supporting member, wherein said angle θ between said second seal portion and said supporting member satisfies 0°<θ<90°.