The invention discloses a method for preparing high-performance graphene by a multi-step weak oxidation-reduction method. The method comprises the following steps: 1) closedly immersing flake graphitein a mixed solution of an organic carboxylic acid solution and a weak oxidant solution for weak oxidation treatment; 2) adding an intercalation agent into the solution obtained after the closed immersion in the step 1), and conducting intercalation treatment; 3) cooling the mixed solution obtained after intercalation treatment in the step 2), adding deionized water, conducting high-pressure treatment and conducting ultrasonic stripping; 4) centrifugally washing the mixed solution obtained after ultrasonic stripping in the step 3), and collecting a slurry with the solid content of 5-10%; 5) drying the collected slurry, and conducting ball-milling to obtain a graphene powder precursor; and 6) conducting high-temperature sintering and thermal reduction on the graphene powder precursor to obtain the graphene. The graphene prepared by the method has excellent performance, high preparation efficiency, and less environmental pollution and industrialization is easy to realize.