The metabolic pathway of 2-deoxy-2-fluoro-D-galactose (FDGal) in mice was studied by 19F NMR. Efficient accumulation of FDGal in liver was demonstrated by NMR, which is consistent with the results of Ishiwata et al. using radioactive 18FDGal. The new discovery is that this fluorinated hexose was converted to 2-deoxy-2-fluoro-D-glucose (FDG) through UDP-FDGal and UDP-FDG apparently by the action of UDP-Gal epimerase.