Pyrolysis behavior of coal gangue and corncob with some additives was studied in a fixed bed reactor. The results showed that with the blending ratio of coal gangue increasing during pyrolysis, the liquid oil yield and the gas yield all decreased, and there were interactions between coal gangue and corncob during co-pyrolysis. Furthermore, the results also showed that just as HZSM-5, medical stone (MS) also had an important influence on the pyrolysis process and could increase the liquid oil yield. Adding Co/MS, Mo/MS, PW12/MS, KCl/MS, CaCl2/MS and Co-Mo/MS could increase the oil yield, and Co/MS had a better effect on liquid oil properties than other additives. Adding CaCl2/MS and Mo/MS also could increase the relative content of H-2 during co-pyrolysis. Adding HZSM-5, KCl/HZSM-5, CaCl2/HZSM-5, SnCl2/HZSM-5, Co/HZSM-5, PW12/HZSM-5 and Mo/HZSM-5 also made the liquid oil yield increase and the gas yield decrease during co-pyrolysis at 500 degrees C and 900 degrees C; and Co/MS also had a better effect on liquid oil properties than other additives.