The invention provides a preparation method of a high-
conductivity hydroxyl / 
epoxy group externally modified 
graphene transparent conductive film. The preparation method comprises the following steps:performing oxidative modification on the two outer 
layers of a three-atomic layer high-quality 
graphene by adopting a specific oxidant to obtain a hydroxyl / 
epoxy group externally modified three-atomiclayer 
graphene material which can be dispersed in a common 
solvent; preparing a film with three-atomic thickness by utilizing a winding bar 
film coating method, a spin-
coating method and the like, and reducing to obtain a high-
conductivity transparent conductive film. An intermediate 
graphene flake layer of an externally modified three-atomic layer graphene material prepared by the method provided by the invention is not oxidized, so that good 
conductivity is still maintained; the external two flake 
layers are modified with a hydroxyl / an 
epoxy group, so that the problems that graphene is difficult to treat and is easy to accumulate are solved. The hydroxyl / epoxy group modified three-atomic layer graphene material endows the graphene with further 
machinability and processability, meanwhile, maintains the performance of the graphene better, and can be applied to the fields such as photoelectric devices and 
energy storage.