A developing device includes a developing chamber, a developer containing chamber located on the lower side of the developing chamber, a partition wall configured to separate the developing chamber and the developer containing chamber, an opening configured to allow the developing chamber and the developer containing chamber to communicate with each other, disposed on the partition wall, a developer conveyance member configured to convey developer from the developer containing chamber to the developing chamber by causing the developer to pass through the opening, disposed on the developer containing chamber. In the developing device, a convex portion which protrudes to the developing chamber side is disposed on the partition wall.