The succulent, narrow leaves of Aloe longistyla are densely arranged in an incurving rosette. Both surfaces are convex. Sparsely scattered spines are present on both surfaces, on the margins and a keel on the outside near the tip.
The blue-grey leaves are covered in a waxy bloom or surface layer. The leaf sap is honey-coloured.
The leaf becomes about 15 cm long and 3 cm wide near the base. There are about 20 to 30 leaves per rosette (Vlok and Schutte-Vlok, 2010; Van Wyk and Smith, 2003; Reynolds, 1974; Jeppe, 1969).