An image-forming device includes a plurality of developer cartridges, a developer moving member and a conveying belt. Each of the developer cartridges includes a casing, a developing roller and a leakage restraining member. The peripheral surface of the developer cartridge has a first peripheral part to convey the developer accommodated in the casing and a second peripheral part. The leakage restraining member is disposed between the casing and the second peripheral part and slidingly contacts the second peripheral part so as to restrain the developer from leaking out of the first peripheral part. The developer moving member moves developer leaked from between the second peripheral part and the leakage restraining member out of a predetermined region at a position opposing the leakage restraining member.