Photosensitive negative resin for direct writing of structures. The present invention relates to a photosensitive negative resin of transition metal oxides comprising an organic content of less than or equal to 20% by weight with respect to the total weight of the resin, an auxiliary inorganic content of less than or equal to 0.01. % by weight with respect to the total weight of the resin and having a refractive index of from about 1.8 to about 2.4. The invention also relates to structures of transition metal oxides obtained by direct writing on the resin of the invention, as well as to the method of preparation of the resin of the invention, to the method of direct writing of the structures of the invention and to the uses both resin and structures. (Machine-translation by Google Translate, not legally binding)