Object of this invention is to provide a photocatalyst deodorizer wherein it is possible to extend the life and increasing an efficiency of filters, and it is possible to activate a photocatalyst which a deodorizing filter carries, by optimizing the positional relation between a tubular light source for emitting light to activatee a photocatalyst and a deodorizing filter, and an emission angle of the tubular light source. Further a photocatalyst deodorizer of this invention makes it easy to maintenance and replacement of filters and the tubular light source.A photocatalyst deodorizer comprising an air purifying portion which is removably arranged in an air passage and constructed from a dust collecting filter, a deodorizing filter carrying a photocatalyst, and a tubular light source arranged in that order in a stack, or constructed from said dust collecting filter, said tubular light source and said deodorizing filter arranged in that order in a stack; wherein said tubular light source is arranged at a position which obtains total surface irradiation of one side of said deodorizing filter, and set at an emission angle which obtains total surface irradiation.