Abstract: The dissolved organic matter (DOM) in natural waters consists of a large number of organic compounds.This paper review the characteristic and measurements of DOM firstly,shows the laser induced fluorescence measurements at monitoring of DOM in water,and discusses in detail the spectral fluorescent signature technique and using Raman scattering as an internal standard to normalize the fluorescence intensity of DOM.Finally,the calibration method of DOM with fumic acid is showed,and many influence factors like temperature,salinity,pH value,fluorescence saturation and fluorescence quenching are discussed.