In the analysis of high performance liquid chromatography (HPLC), the qualification of chromatographic peak can be carried out by the methods of adding standard, comparing retention time and absorption spectrum etc. This paper reports a simple and practical method for measurement of absorption spectrum of HPLC peak by ultraviolet and visible variable wavelength detector. A BASIC program was edited with Shimadzu C-R4A data processor. Stopping the pump at the retention time we use the program to analyse absorption spectrum of the peak and the absorption spectrum of standard (Cr, PU, UA) by Shimadzu UV-2201 UV-VIS recording spectrophotometer and the absorption spectrum of standard (-S) with sample (-T) by this method are presented. The figure shows that the absorption spectra of the samples of Cr, PU and UA almost completely overlapped with those of the standards. The results showed that this method is reliable.