Disclosed is a solid electrolyte for a dye-sensitized solar cell, which includes a three-dimensional porous thin film made of a hydrophilic polymer material, and a dye-sensitized solar cell using the same. More particularly, the present invention provides a high-efficient dye-sensitized solar cell, in which polymer nanofibers having high specific surface area are used in an electrolyte layer to effectively induce an increase in photocurrent, thereby increasing the amount of electrolyte impregnated. When the porous film prepared by the method of the present invention is used as a solid electrolyte for a dye-sensitized solar cell, a process of forming an electrolyte inlet and sealing the inlet is not required, which simplifies the entire process, compared to an existing dye-sensitized solar cell using a liquid electrolyte.