The invention provides a method for preparing polyetheretherketone with a phthalazone pyridine structure. The method comprises the steps: adding a phthalazone pyridine monomer, difluorobenzophenone, potassium carbonate, sodium carbonate, cyclobutyl sulfone and toluene into a reactor, and heating the temperature of the materials to a refluxing temperature under nitrogen protection, so as to promote a salt forming reaction of a bisphenol monomer; distilling off toluene after azeotropic dehydration is completed; heating the reactor to carry out a polymerization reaction; pouring a polymer solution into hot water, so as to precipitate a white and fibrous polymer; and subjecting the white and fibrous polymer to washing, filtering and baking, then, dissolving the polymer in chloroform, and then, carrying out settling in ethanol, thereby obtaining the polyetheretherketone with the phthalazone pyridine structure. Through introducing the phthalazone pyridine with a distorted noncoplanar structure, crystallization of the polymer can be lowered, and meanwhile, a vitrification temperature for the polymer cannot be lowered, so that heat resistance of the polyetheretherketone is guaranteed, and the dissolubility of the polyetheretherketone is improved.