Abstract: Advantages of second-generation biodiesel are reviewed on the basis of literatures. The preparation principle for second-generation biodiesel is described，and three main production processes are summarized as the direct hydrodeoxygenation of oils and fats，the hydrodeoxygenation followed by hydroisomerization and the refining blended with diesel fuel. Furthermore，catalysts for hydrodeoxygenation and hydroisomerization involved in the preparation process are also summarized. Problems in the development of second-generation biodiesel are discussed，and corresponding solutions are proposed.