NO (Nitric Oxide) is a colorless and odorless gas that is difficult to dissolve in water.It is mainly derived from the combustion of motor vehicle ex haust and fossil fuels,which can cause acid rain and damage the human respirato ry tract.Therefore,it is of great environmental significance to monitor NO con centration.This paper introduces the principle of NO concentration detection ba sed on Lambert-Beer′s law and sets up an experimental platform.Then the experi m ental study on the characteristics of Hamamatsu L9455-1pulse xenon lamp for th e NO concentration detection has been carried out.The fluctuation of light sourc e,integral time of light source collection,average times and other practical p roblems occurred in the experiment have been studied carefully,and then the cor responding solutions have been put forward respectively.Finally,the most reaso nable operating parameters of light source have been obtained,of which the puls e frequency of the light source is 5Hz,the integration time of the spectrometer is 200ms,and the average number of times of the spectral data is 10times.The experimental results are compared with the deuterium lamp light source,which s hows the advantages of L9455-1in portable NO concentration detection.Then the above results have been applied to the NO absorbance detection of different conc entrations.The detection results show that using the parameters obtained in the study to set the working index of L9455-1pulse xenon lamp can obtain relative l y accurate NO absorbance,which can lay a good foundation and be fully prepared for the entire portable detection system to measure the NO concentration accurat ely.