We report a comprehensive light element (Li, C, N, O, Na, Mg, and Al) abundance analysis of three solar-type main sequence (MS) dwarfs and three red giant branch (RGB) clump stars in the Hyades open cluster using highresolution and high signal-to-noise spectroscopy. The abundances have been derived in a self-consistent fashion, and for each group (MS or RGB), the CNO abundances are found to be ...