1. Fractions of kenaf DLA have been cleaved by metallic sodium in liquid ammonia. By GLC among the cleavage products have been found phenols the structure of which indicates the presence in the initial lignins of p-hydroxyphenyl-, guaiacyl-, and syringylpropane units with free OH groups in the α and γ positions of the side chain of the aromatic nucleus. 2. It has been found that with the passage from DLAK-I to DLAK-III the number of phenolic substances obtained on cleavage decreases, and the amount of syringyl structures decreases simultaneously, which may be due both to the heterogeneity of the distribution of the lignin in the plant tissue and to its localization in morphological elements of the latter accessible to the reagent to different degrees.