A developing cartridge, comprising: a cylindrical developing roller that develops, by way of a developer, an electrostatic latent image that is formed on an image bearing member; a developer regulating member that regulates a thickness of developer carried on the developing roller; and a frame that rotatably supports the developing roller, and supports the developer regulating member, wherein the frame has a developing roller support section (214a1) that rotatably supports an outer peripheral face (210d6) of at least one end of the developing roller, and the developing roller support section (214a1) is an integral part of the frame, and protrudes from the frame towards an inner side of the frame in the axial direction of the developing roller, characterized in that the developing roller support section (214a1) has a clearance at a position that, when viewed in an axial direction of the developing roller, overlaps a contact region at which the developing roller is in contact with the image bearing member, the developing cartridge further comprises a magnet member disposed in an inner section of the developing roller, a lubricant is interposed between the developing roller and the developing roller support section (214a1), and the developing roller support section (214a1) has a lubricant introduction section (214c3) in which another clearance that becomes gradually narrower, in a rotation direction of the developing roller, as approaching a contact section with the outer peripheral face (210d6) of the developing roller, is formed between the developing roller support section (214a1) and the outer peripheral face (210d6) of the developing roller, the lubricant introduction section (214c3) being provided upstream of the contact section in the rotation direction. a cylindrical developing roller that develops, by way of a developer, an electrostatic latent image that is formed on an image bearing member; a developer regulating member that regulates a thickness of developer carried on the developing roller; and a frame that rotatably supports the developing roller, and supports the developer regulating member, wherein the frame has a developing roller support section (214a1) that rotatably supports an outer peripheral face (210d6) of at least one end of the developing roller, and the developing roller support section (214a1) is an integral part of the frame, and protrudes from the frame towards an inner side of the frame in the axial direction of the developing roller, characterized in that the developing roller support section (214a1) has a clearance at a position that, when viewed in an axial direction of the developing roller, overlaps a contact region at which the developing roller is in contact with the image bearing member, the developing cartridge further comprises a magnet member disposed in an inner section of the developing roller, a lubricant is interposed between the developing roller and the developing roller support section (214a1), and the developing roller support section (214a1) has a lubricant introduction section (214c3) in which another clearance that becomes gradually narrower, in a rotation direction of the developing roller, as approaching a contact section with the outer peripheral face (210d6) of the developing roller, is formed between the developing roller support section (214a1) and the outer peripheral face (210d6) of the developing roller, the lubricant introduction section (214c3) being provided upstream of the contact section in the rotation direction.