The invention relates to a method for preparing platinum material for a dispersion strengthened thermoelectric couple negative electrode fine wire. The method comprises the steps that a zirconium oxychloride reagent is added to a high-purity platinum solution with impurities removed, the solutions are stirred, so that zircon salt is dissolved in the solution of the pure platinum, the acidity of the solution is adjusted, zircon is hydrolyzed and turned into fine particles of zirconium nitrate, platinum is reduced, and the prodromic material, namely the platinum material containing zirconium oxide, for preparing the fine wire is obtained after calcination. The platinum material is machined into the fine wire, the strength of extension of the fine wire is higher than that of a common platinum wire, the zirconium content of a dispersion strengthened platinum wire is 0.12 percent, the resistance ratio is larger than or equal to 1.3920, and the method is suitable for machining Pt-Rh 10 or Pt-Rh 13 thermoelectric couple negative electrode fine wires.