The invention belongs to the field of film separation technique, and particularly relates to a 
gas separation film based on 
carbon nanotube / 
graphene oxide-
polyether block amide. A preparation method of the 
gas separation film comprises the following steps of obtaining a 
carbon nanotube / 
graphene oxide novel nanometer carbon structure by a chemical oxidation method, and enabling a certain amount of 
carbon nanotube / 
graphene oxide to be dispersed ultrasonically in a 
mixed solution of 
ethanol and water (in a 
mass ratio of the 
ethanol to the water being 7 to 3) so as to obtain uniform dispersion fluid A; then dissolving a certain amount of 
polyether block amide into a solution of 
ethanol and water, with the same amount as the 
mixed solution of the ethanol and the water, and performing stirring until the 
polyether block amide is completely dissolved so as to obtain dispersion fluid B; and mixing the dispersion fluid A with the dispersion fluid B, allowing the mixed dispersion fluid to stand for deaeration, pouring the mixed dispersion fluid after deaeration into a culture dish, and performing 
drying and film forming so as to obtain the 
gas separation film based on the carbon 
nanotube / graphene oxide-polyether block 
amide. Compared with polyether block 
amide separation films, the gas separation film based on the carbon 
nanotube / graphene oxide-polyether block 
amide provided by the invention has better 
heat stability, higher gas 
permeation coefficients and higher separation coefficients, and has important application prospects in the field of gas separation films.