Abstract: The effect of mineral matter on pyrolysis and product evolution of oil shale was studied by GC and FT-IR. Hudian oil shale was treated by sequential washing with HCl and HF/HCl. The results show that carbonate has catalytic effect on conversion of organic carbon and hydrogen from Kerogen to shale oil, which is inhibited by silicate. The H/C atomic ratio in shale oil increases in both carbonate-free and silicate-free oil shale. Carbonate enhances gas yield and inhibits oil yield, while silicate is just opposite. The contents of CO₂ and H₂ decrease but CO increases in both carbonate-free and silicate-free oil shale. Carbonate can inhibit generation of hydrocarbon in gas product while silicate has catalytic effect on it. All the carbonate and silicate can increase the length and degree of branching aliphatic side chains in shale oil and improve aromatization of the solid product from shale.