Abstract: One of pyrolysis parameters,S1 is a key parameter for free hydrocarbon content in shale oil characterization and its accuracy can directly affect the credibility of the oil shale resources potential evaluation result.Influenced by experimental analysis technology,the measured S1 needs light and heavy hydrocarbon loss of correction.Through parameters comparison before and after pyrolysis analysis of Lucaogou formation in Santanghu basin,the correlation coefficient of heavy hydrocarbon has been determined to be 1.2.By comparing the maturity and the correction coefficient curve of mudstone of Qingshankou formation in Songliao basin,the correlation coefficient of light hydrocarbon in Lucaogou formation in Santanghu basin has been determined to be 0.8.Through comprehensive analysis of the experimental value and light and heavy hydrocarbon correction coefficients,the pyrolysis parameter of mud shale S1 in Lucaogou formation after correction is 3 S1.