A developing device (10, 110) comprising: a developing roller that is rotatable about a first axis extending in an axial direction; a first gear for rotating the developing roller; a second gear that is in mesh with the first gear and is rotatable in a first direction about a second axis extending in the axial direction; a coupling that is rotatable about the second axis and is rotatable both in the first direction and in a second direction opposite to the first direction, the coupling including a coupling gear; a clutch positioned between the coupling and the second gear in the axial direction and that rotates together with the coupling, the clutch being configured to come into engagement with a portion of the second gear and cause the second gear to rotate in the first direction together with the coupling gear when the coupling rotates in the first direction, the clutch being configured to neither come into engagement with the portion of the second gear nor cause the second gear to rotate together with the coupling when the coupling rotates in the second direction; and a moving gear that is in mesh with the coupling gear and is rotatable both in the first direction and the second direction about a third axis extending in the axial direction, the moving gear being movable while being in mesh with the coupling gear between a first position where the moving gear is out of mesh with the first gear and a second position where the moving gear is in mesh with the first gear, the moving gear moving to the first position when the coupling gear rotates in the first direction and to the second position when the coupling gear rotates in the second direction, wherein when the coupling gear rotates in the first direction, the moving gear moves to the first position and goes out of mesh with the first gear, and the first direction rotation of the coupling gear causes the second gear to rotate in the first direction together with the coupling gear with an aid of the clutch and causes the first gear being in mesh with the second gear to rotate in the second direction; and wherein when the coupling gear rotates in the second direction, the moving gear moves to the second position and comes into mesh with the first gear, and the second direction rotation of the coupling gear causes the moving gear, being in mesh with the coupling gear, to rotate in the first direction and to cause the first gear, being in mesh with the moving gear, to rotate in the second direction. a developing roller that is rotatable about a first axis extending in an axial direction; a first gear for rotating the developing roller; a second gear that is in mesh with the first gear and is rotatable in a first direction about a second axis extending in the axial direction; a coupling that is rotatable about the second axis and is rotatable both in the first direction and in a second direction opposite to the first direction, the coupling including a coupling gear; a clutch positioned between the coupling and the second gear in the axial direction and that rotates together with the coupling, the clutch being configured to come into engagement with a portion of the second gear and cause the second gear to rotate in the first direction together with the coupling gear when the coupling rotates in the first direction, the clutch being configured to neither come into engagement with the portion of the second gear nor cause the second gear to rotate together with the coupling when the coupling rotates in the second direction; and a moving gear that is in mesh with the coupling gear and is rotatable both in the first direction and the second direction about a third axis extending in the axial direction, the moving gear being movable while being in mesh with the coupling gear between a first position where the moving gear is out of mesh with the first gear and a second position where the moving gear is in mesh with the first gear, the moving gear moving to the first position when the coupling gear rotates in the first direction and to the second position when the coupling gear rotates in the second direction, wherein when the coupling gear rotates in the first direction, the moving gear moves to the first position and goes out of mesh with the first gear, and the first direction rotation of the coupling gear causes the second gear to rotate in the first direction together with the coupling gear with an aid of the clutch and causes the first gear being in mesh with the second gear to rotate in the second direction; and the moving gear moves to the first position and goes out of mesh with the first gear, and the first direction rotation of the coupling gear causes the second gear to rotate in the first direction together with the coupling gear with an aid of the clutch and causes the first gear being in mesh with the second gear to rotate in the second direction; and wherein when the coupling gear rotates in the second direction, the moving gear moves to the second position and comes into mesh with the first gear, and the second direction rotation of the coupling gear causes the moving gear, being in mesh with the coupling gear, to rotate in the first direction and to cause the first gear, being in mesh with the moving gear, to rotate in the second direction. the moving gear moves to the second position and comes into mesh with the first gear, and the second direction rotation of the coupling gear causes the moving gear, being in mesh with the coupling gear, to rotate in the first direction and to cause the first gear, being in mesh with the moving gear, to rotate in the second direction.