Precursor gel fibers have been prepared by extruding cellulose acetate spinning solutions into transition metal (Ti, Nb, Ta) acetone solution as a coagulation bath. Gel formation must be due to the coordination of metal to OH and CO groups on the pyranose ring. The resultant gel fibers have been converted into nitride fibers by pyrolyzing the precursor in NH3 gas flow at temperatures lower than for powder processing. The precursor gel can give a molecular scale mixture of metal and carbon sources. NbN fiber gave a superconductance at around 13 K.