The present invention relates to a catalyst for preparing biodiesel, and a method for preparing biodiesel using the same. More specifically, the present invention relates to a catalyst for preparing biodiesel, which prepares biodiesel from a feed containing vegetable oil using a catalyst containing a metal phosphorus compound. The catalyst for preparing biodiesel according to the present invention uses a metal phosphorus compound, thereby enhancing preparation activity of HBD even without continuous injection of sulfides, and enabling production of high quality HBD with a low pour point due to the simultaneous procession of hydrogenation and isomerization reactions.