A kind of polymer electrolyte and an other kind of macro molecular polymer electrolyte or non-electrolyte polymer capable of ionizing opposite charge in certain proportion are dissolved in water to prepare dilute solution. The solution is filled into an electrolyzer capable of forming homogeneous electric field and the polymer electrolyte in the water solution is ionized to produce charged polymer ions. Meanwhile, the polymer ions under the action of the electric field immigrate from one electrode to the other to generate density gradient. With the electrolysis and evaporation of the water solution, gradient of polymer mixture components is formed in the electric field direction; and after finishing electrolysis and evaporation, gradient polymer mixture material with continuously changingcomponent is obtained. The method of the present invention is simple and easy to control. By means of controlling voltage, temperature and other conditions, polymer material of different gradient maybe produced.