The present invention relates to a novel ruthenium-based dye and a method for preparing the same, and more specifically, to a bipyridine-based ruthenium dye which prevents an interaction with I 2 of an electrolyte by introducing a hydrophobic group combined with oxygen into a ligand site; exhibits an improved photoelectric conversion efficiency and long-term stability, thereby greatly improving efficiency and lifespan of a solar cell; and is synthesized by a relatively simple method, thereby reducing its manufacturing costs. The bipyridine-based ruthenium dye of the present invention is used as a dye in a dye-sensitized solar cell (DSSC) and thus has higher efficiency and better long-term stability than existing dyes, thereby significantly improving efficiency of the solar cell.