To provide a built-up type closet, simple in structure to be easily built up, presenting high-class appearance and presenting the generation of dew condensation.

In this built-up closet, a back horizontal frame material 5A having linear grooves 7a, 7b on the rear edge part and both side edge parts of a base plate 1 and both side horizontal frame materials 5B, 5B are fixed, the lower end part of a back plate 2 is inserted in the linear groove 7a of the back horizontal frame material 5A to be supported and erected. On the other hand, both side vertical frame materials 6, 6 are fixed to the front both side edge parts of the back plate 2, and the lower ends of vertical linear grooves 8 provided in the front surfaces of the vertical frame materials 6, 6, are connected at right angles to the rear ends of the horizontal linear grooves 7b, 7b of the both side horizontal frame materials 5B, 5B. The lower end edge part and rear end edge part of both side plates 3, 3 are inserted in the linear grooves 7b, 8 to be supported, and then a top plate 4 is stretched and fixed to an upper end opening part surrounded with the back plate 2 and both side plates 3, 3. The base plate 1, the back plate 2, both side plates 3, 3 and the top plate 4 are formed of paulownia wood material.