A method for the simultaneous determination of codeine, morphine, thebaine, papaverine and narcotine in pericarpium papaveris by gas chromatography with wide bore capillary column is described. The major components in pericarpium papaveris were extracted with methanol and chloroform by supersonic extraction and evaporation. The residue was dissolved in methanol. The resulting solution was used for analysis. The conditions for determination were: FID detector, HP-1 capillary column, 5 m x 0.53 mm x 2.65 microns film, column temperature 260 degrees C, The method requires 10 minutes for the whole analysis. The average recoveries of codeine, morphine, thebaine, papaverine and narcotine in the sample were 94.0%, 96.5%, 93.8%, 91.0% and 91.4% respectively. The relative standard deviations were from 0.92% to 2.75%. The advantages of this method are simple, rapid, accurate and sensitive.