Abstract: Heavy oil exploitation benefit can be improved by CO2 stimulation process. Any horizontal well CO2 huff and puff should be selected by the geological conditions and performance of candidate wells. Combined with related data and numerical simulation results, comprehensive consideration of reservoir properties, fluid characteristics and horizontal well length, this paper put forward the horizontal well location selection evaluation index system and grading method suitable for heavy oil reservoirs by CO2 huff and puff process, and concrete approaches and steps by means of fuzzy evaluation theory and information entropy theory.31wells data of CO2 stimulation in X reservoir were used to verity the proposed method. The verification result is accordant with the actual situation, showing that the proposed method is feasible, and can provide reference and guidance for similar heavy oil reservoir development with horizontal well CO2huff and puff process