The invention relates to a multilevel variable-frequency corrosion method for an anode foils of aluminum electrolytic capacitor, in particular to a corrosion process for anode foils of aluminum electrolytic capacitors, which comprises the following steps: removing greasy dirt and oxide film on the surface of the aluminum foils; performing multilevel AC electrolytic corrosion, intermediate and post treatment orderly. The multilevel variable-frequency corrosion method is characterized in that the AC electrolytic corrosion is performed in mixed liquid of 0.1 to 10wt% sulfate and 3 to 20wt% hydrochloric acid at 25 to 60 DEG C; the frequency of the AC electrolytic corrosion is 5 to 40Hz; the frequency values of the AC electrolytic corrosion at each level are different. With the adoption of different frequency and multilevel corrosion process, the multilevel variable-frequency corrosion method for the anode foils of aluminum electrolytic capacitor has the advantages of high specific volume, excellent mechanical properties and applicability to aluminum electrolytic capacitors.