To provide a technology for efficiently and inexpensively manufacturing a wall surface material and a ceiling material having a ceramic substrate as a base, which is practically resistant to ultraviolet rays of 253.7 nm radiated by a UV germicidal lamp used for a clean room or the like.

The ceramic substrate having been subjected to smoothing foundation processings of a filler processing, UV sealer processing and sanding processing based on a heretofore known technology, is used, and on the surface thereof, an acrylic enamel layer 4 for coloration and concealment is arranged as a first layer with a dried film thickness of 20-40 μm, and furthermore, a fluororesin enamel layer 5 with the same hue as that of the first layer mainly for coloration and practically resisting to the ultraviolet rays is arranged as a second layer with a dried film thickness of 7-15 μm. These two enamel layers 4, 5 with the same hue are arranged, thereby obtaining an objective ceramic decorative sheet efficiently inexpensively.