An ultraviolet ray detection device (10) detects an ultraviolet ray which hastransmitted through a test sample (15) or has been reflected by the test sample(15) from light rays containing at least ultraviolet rays. The ultraviolet raydetection device includes: spectral means (19) for separating an ultravioletray from the light rays； and photo detection means (20) having a photoelectricplane formed by elements selected from In, Ga, N, Al, O, and Cs for detecting onlythe ultraviolet ray separated by the spectral means (19).
