An image forming device includes a main casing, a support member, a plurality of developing cartridges, a handle provided to the support member, and a pair of interfering parts provided at both ends of the support member. Each developing cartridge includes a casing and a developing member supported by the casing. A gap between the pair of interfering parts is narrower than a length of the developing member, and the pair of interfering parts is located between the handle and one of the developing cartridges. Each of the interfering parts has a higher height than the handle.