Preparation method of metal chelate and high-temperature polymer fracturing fluid

The invention provides a preparation method of a metal chelate and a high-temperature polymer fracturing fluid, and the method comprises the following steps: carrying out chelation reaction on a high-valence metal substance and a ligand substance in water to obtain the metal chelate, wherein metal in the high-valence metal substance is zirconium and/or titanium, the ligand substance comprises a weak coordination substance and a strong coordination substance, the weak coordination substance is polyhydric alcohol and/or polyhydric alcohol amine, and the strong coordination substance is organic acid and/or organic acid salt. The high-temperature polymer fracturing fluid provided by the invention mainly comprises a polymer thickening agent, the metal chelate cross-linking agent, a cleanup additive, a clay stabilizer and a demulsifying agent, and can still realize the effect of delaying cross-linking under a high-temperature condition. The fracturing fluid has the advantages of high temperature resistance, shearin