An image-forming device includes a main casing, a process casing, a photosensitive member, a charger, a first duct member, a fan, and a duct moving unit. The process casing is accommodated in the main casing and removably mounted thereon. The process casing has a casing inlet formed therein. The photosensitive member is disposed in the process casing. The charger is disposed in the process casing for charging a photosensitive member. The first duct member has a duct outlet. The fan blows air on the charger through the duct outlet of the first duct member and the casing inlet. The duct moving unit moves the first duct member between a first position in which the duct outlet of the first duct member is adjacent to the casing inlet formed in the process casing, and a second position in which the duct outlet is separated farther from the casing inlet than in the first position.