Abstract: The carbon skeleton structure of oil shales from Gansu Yaojie mine was characterized by the ¹³C solid-state NMR; the chemical structure parameters of cluster in the oil shales, such as average number of carbons, aromatic carbons, aliphatic carbons and aromatic rings, were determined. TG-FTIR tests were used to obtain the yields of pyrolysis products. Considering the cluster chemical structure parameters determined by ¹³C solid-state NMR, the release of pyrolysis products was simulated by FLASHCHAIN. The simulation results are in good agreement with the TG-FTIR tests, proving the rationality of the model proposed.