An expandable trailer having a lower body portion having a first floor, a front wall, a back wall and a pair of opposite side walls. The trailer also has an upper body portion that is disposed over the lower body portion. The body portion has an upper segment and a lower segment that is connected to the lower body portion. The upper segment has a front wall, a back wall, a pair of opposite side walls, and a roof. The upper segment is movable relative to the lower segment such that the upper segment has a raised and lowered position relative to the lower body portion. The trailer may contain multiple floors defining separate living areas. The trailer may also have expandable rooms in the lower body portion which are slidingly retained within the lower body portion and provide additional room within the lower body portion.