Simulation experiments carried out with the source rock samples from the Tarim Basin fail to reflect or describe the hydrocarbon generation processes which these samples experienced before they reached the present buried depths due to relatively large buried depths and high maturity of most main source rocks. In consideration of this tough problem the principle and method for restoring the original parameters of chemical kinetic models for the samples studied are derived and constructed based on the chemical kinetic models calibrated with the data of thermal simulation experiments. The results indicate that quite a number of components with low activation energy in organic matter of deeply buried samples have been consumed by the reactions of hydrocarbon generation during the earlier evolution process. Therefore, it is necessary to recover the consumed parts so as to describe objectively the whole process and amount of generated hydrocarbon.