Photoacoutic detection system of solid powder and signal analysis methods,which are used to distinguish material component quickly without damage and improve detection ability,are researched. Nonresonant cylinder photoacoutic cell is designed based on the theory of R-G. The system consists of high power xenon lamp,chopper,lock-in amplifier,grating monochromator,data acquisition system and photoacoustic cell. The methods of enhancing the amplitude of signal are used to improve resolution ability,such as choosing high sensitivity sound detector,increasing permeation rate,designing low noise and high signa-to-noise ratio circuit. The experimental system is stable and reliable. Wavelet is applied to improving analysis ability. It provides identification evidence conveniently and quickly by the photoacoustic signal analysis of nitrocompound,copper sulphate and mixture.