Xenon flash lamp is used by most analytical instruments and medical equipments as light sources whose spectral characteristics exert a tremendous influence on the property of instruments and medical equipments. In order to study the effects of pulsed Xenon discharge circuit parameters and geometric parameters on the spectral characteristics, theoretical analysis has been conducted to Xenon lamp emitting process with the gas discharge theory. The spectroscopic detection system has been designed to conduct experimental detection to the spectral characteristics of pulsed Xenon lamp with different parameters. The experimental results show that the emission spectra of Xenon flash lamp contain both line and continuous radiation. The line spectrum results from the electron energy gap transition, while the cw radiation related to ionic recombination and bremsstrahlung. The relative spectral intensity increases linearly with the discharge voltage, and has a positive correlation with storage capacitor. When low discharge voltage, the shorter the arc length, the higher the relative spectral intensity .while the discharge voltage becomes higher, the result is reversed. The work in this paper has great significance for xenon flashlamp on the parameters selection and industrial application.