Abstract: The gasification cogeneration system using biomass feedstocks as input energy has the potential to generate clean heating in rural areas of northern China and meets the "carbon neutralization" target. The performance of three kinds of typical biomass feedstocks（corn cob, wheat straw and bark） under different mixing ratios was compared and analyzed, and the suggestions of corresponding mixing ratios under different scenarios using performance evaluation index as a reference were proposed. Results show that the optimal air equivalence ratio（0.325） can be acquired at the mixing ratio（B） of 5∶5∶5, and the corresponding cold gas efficiency is 79.65%. The highest calorific value of syngas is 4.691 MJ/m~3 at the mixing ratio of 1∶5∶1, while the lowest biomass feedstock consumption is 20.1 kg/h at the mixing ratio of 1∶5∶10. The highest waste heat of jacket water and exhaust gas are 15.94 kW and 17.6 kW at the mixing ratio of 1∶5∶10, meanwhile the highest cooling capacity is 6 kW. For the application scenario with high energy efficiency requirements but insensitive to price, the recommended mixing ratio is 1∶5∶10, and corresponding energy and exergy efficiency are 22.24% and 15.44% respectively.