The invention relates to a refining process of a polymer material, in particular to a process for refining a crude polyethylene ketone ketone product through sodium gluconate. The process includes the steps of stirring a certain amount of crude polyether ketone ketone product in a dichloromethane solution containing diphenyl sulfone in a return flow mode, adding a sodium gluconate water solution to be stirred in a return flow mode, conducting cooling and filtering, conducing return flow washing through a mixed water solution of glycolic acid and formic acid, and conducting filtering and drying to obtain a pure polyether ketone ketone product. By adding diphenyl sulfone to dichloromethane, the swelling capacity of dichloromethane is effectively improved, polyether ketone ketone molecular chains closely wrapping catalyst impurities can be thoroughly distracted, and impurity ions are dispersed in an organic phase; meanwhile, through the efficient metal chelating capacity of sodium gluconate, metal ions are continuously captured from the organic phase, and therefore the efficient removal of Al<3+> in the crude polyether ketone ketone product is achieved.