Abstract: Gas injection especially carbon dioxide injection may cause asphaltene deposit. In this paper，in order to analyze the
deposition trend and the influence of deposition on oil recovery，the multiphase multicomponent numerical model considering
asphaltene deposition，adsorption and plugging is established. Then，based on long core flooding experiment，the fitting data
indicate that the oil recovery calculated by this numerical model is closer to experiment results than that by regular model.
Finally，the asphaltene deposition tendency during CO2 flooding is discussed，which indicate that higher accumulation of
deposited asphaltene is shown primarily at the injection part of the core. Meanwhile，adsorbed asphaltene，also accumulated
at the inlet side of the core，is desorbed gradually with the gas injection. asphaltene deposition front accord with injected gas
front，which indicates that injected carbon dioxide is the main reason for asphaltene deposition.

Key words: asphaltene, carbon dioxide injection, depositionrule, numerical simulation