The invention discloses a curing delayed mixed solution, which comprises: 0.1-0.5% of polyacrylamide, 0.05-0.5% of a chromium cross-linking agent, 0-0.3% of a cadmium ion stabilizer, and the balance of water, wherein the chromium cross-linking agent is selected from chromium acetate, chromium lactate or/and paraffin-coated chromium acetate, and the cadmium ion stabilizer is selected from ethylenediamine tetra(methylene phosphonic acid)sodium, sodium EDTA, sodium potassium tartrate, hydroxyethylidene diphosphonic acid or/and sodium metaphosphate. According to the present invention, the mixed solution can be used for hydraulic packers with any structural models, and can effectively prevent hydraulic packers from failure caused by hydraulic oil leakage (the application method comprises: filling the closed chamber of a hydraulic packer with the mixed solution, and setting for more than 9 h until curing to achieve a solid-state non-flowing material) sp as to prolong the effective period ofthe hydraulic packer, wherein the setting method and the unsealing method of the hydraulic packer are not changed, and the application prospect is broad.