3-D fluorescence spectra and excitation-emission matrix(EEM) of human nsopharyngeal tissures were obtained to exploit the endogenous fluorophores of human normal and cancerous nasopharyngeal tissues in vitro,respectively.The excitation wavelength was varied from 260 to 500 nm in 20 nm increments,and the fluorescence emission spectra were recorded from 280 to 700 nm.The primary fluorescence peaks occurred at the excitation-emission wavelength paris of 260-605,300-330,340-380,340-460 and 460-525 nm,which can be attributed to the ceroid,aimno acids,collagen,reduced nicotinamide adenine dinucleotide or reduced nicotinamide adenine dinucleotide phosphate,and flavin adenine dinucleotide,respetively.Experimental results indicated that the significant fluctuation for the intensities of emission peaks dramatically varied with the incident angula of excitation light,while the minimal photobleaching occurred for EEM measurment.