Phenolic leaf exudate constituents from Aloe turkanensis and A. scabrifolia were examined by TLC and HPLC. The chromatographic patterns clearly differentiated between the two species, which had originally been described as one, although geographically separated. Some of the chromatographic zones could be equated with known compounds, but others were characterized only by their colour reaction and UV absorption values. Comparisons were made with chromatographic patterns of other Aloe species.