A developing device includes a developing roller to rotate in a predetermined direction of rotation and opposed to or in contact with an image bearer to form a development range, a cover to cover the developing roller downstream from the development range in the predetermined direction of rotation, a sheet member cantilevered by the cover to contact the developing roller with a flat face of the sheet member while trailing along the predetermined direction of rotation at a position downstream from the development range. The cover includes a large gap portion to form a first gap in a first predetermined range in the predetermined direction of rotation and a small gap portion disposed adjacent to and downstream from the large gap portion in the predetermined direction of rotation to form a second gap smaller than the first gap in a second predetermined range in the predetermined direction of rotation.