The invention discloses a recovery method for invalid alkaline copper-containing etching liquid.The recovery method at least includes the following steps that a, an oxidizing agent is added into the invalid alkaline copper-containing etching liquid, and the mixture is reacted for 8 min-10 min at the room temperature; b, ammonium diethyldithocar-bamate is added into the invalid alkaline copper-containing etching liquid to obtain brown sediment; c, the brown sediment is placed into a second container, then ammonia water is added into the second container till the brown sediment is completely dissolved, and blue sediment is obtained; d, the blue sediment is placed into a third container, a sulfuric acid solution is added into the third container till the blue sediment is completely dissolved, and the mixture is continuously stirred; e, the solution is heated to obtain blue crystals.The recovery method has the advantages that impurity ions are not led in, and the chemical composition of the etching liquid is not damaged; the ammonium diethyldithocar-bamate is recycled and can be reused, and production cost is low; recycled copper sulfate is high in purity; the concentration of copper in the invalid alkaline copper-containing etching liquid can be controlled as required; secondary pollution is avoided.