The invention discloses a method for recovering and treating a chemical nickel waste liquid by adopting a composite double-sided electrode. The two sides of the composite double-sided electrode serveas an anode surface and a cathode surface respectively, the cathode surface and an external breaking anode form an electrolytic circuit, the anode face and another external cathode form another electrolytic circuit, and the two electrolytic circuits simultaneously treat the chemical nickel waste liquid by using a pulse electrolysis method to synchronously decompose a complexing agent in the chemical nickel waste liquid and recover a nickel-phosphorus alloy. The method for recovering and treating the chemical nickel waste liquid by adopting the composite double-sided electrode has the advantages that a metal oxide composite electrode is utilized to break a complex state of nickel ions in the waste liquid, the two electrodes of the composite double-sided electrode are mainly utilized to forman electrosorption reaction and an electroreduction reaction respectively, and the adsorption reaction comprises the step that an anode capacitor enriches the ions in the chemical nickel waste liquidat a carbon-based porous anode-solution interface.