In this paper, we report the `Ultraviolet-Visible-Infrared Wide Band Tunable Pulse Laser' has been used in identifying the criminal's fingerprint. Different contaminator and secretion of fingerprint in different carrier can be reappeared by illuminating with different wavelength of laser beam. Separating off the laser beam from its induced fluorescence beam with different optical filter, the clear high signal noise ratio fluorescence picture is obtained in a dark background. A series of fluorescence fingerprint picture excited by different wavelength laser light is taken in our Lab. In addition, by using the wide band tunable laser, we test different fluorescence powder or reagent, which sensitivity in different wavelength, a lot of clear fluorescence picture is taken by correspondent wavelength laser beam injection. In this way, the wide band tunable laser offers a wide band of wavelength for develop high sensitivity new fluorescence powder or reagent in chemical field.