Background : Rehmannia glutinosa is a perennial herb belonging to the family Scrophulariaceae. Its roots have been utilized as a traditional medicine but the aerial parts (flower, flower stalk, leaf) were not used. In this paper, we aimed to determine the content of three compounds [aucubin, catalpol, and γ-aminobutyric acid (GABA)] in different organs of R. glutinosa. Methods and Results : The flower, flower stalk, leaf, and root of R. glutinosa were harvested in the end of August. The aucubin and catalpol were analyzed by LC/MS, whereas GABA was analyzed by GC/MS. The aucubin content was the highest in the leaf, while catalpol and GABA were the highest in the flower. The aucubin content of in the leaf was 1.43, 0.81, and 1.07 ㎎/g, respectively. The catalpol content of flower in Dakang, Tokang, and Suwon 9 was 41.06, 28.78 and 37.48 ㎎/g, respectively. The GABA content of flower in Dakang, Tokang, and Suwon 9 were 0.79, 0.76 and 0.65 ㎎/g, respectively. Conclusions : The contents of aucubin, catalpol, and GABA were higher in leaf and flower than that of root. This study provides the important information of R. glutinosa leaf and flower as a potential supplement.