Synthetic γ-hydroxyglutamic-α-C14 acid was found to be extensively catabolized in the intact rat and to give rise to both labelled glutamic and aspartic acids. The results obtained are in agreement with a previously proposed theory that γ-hydroxyglutamic acid may be converted to glutamic and aspartic acids by two distinct metabolic routes. The fact that only a small amount of radiocarbon was found in the tissue hydroxyproline suggests that the conversion of γ-hydroxyglutamic acid to hydroxyproline, if it does occur, is of minor importance.