The main components of the leaf wax of Cupressus dupreziana were reported, with the closely-related Cupressus sempervirens re-examined for comparative purposes, and the heartwood of both species also studied to complete the comparison. Petrol extracts of the leaves (LP) of the two species were fractionated into neutral and free-acid compounds by Na₂CO₃ treatment; the neutral fraction was chromatographed (Al₂O₃ grade II) to obtain n-alkanes and secondary alcohols, and saponification of LP yielded fatty and ω-hydroxy acids. Petrol extracts of the heartwood (HP) were fractionated in the same way. All compounds were identified by GLC and GC/MS. This comparative study showed a great similarity between the n-alkane compositions (main compounds: tritriacontane and pentatriacontane, consistent with Cupressaceae family) and total acid compositions of the two species. On the other hand, their secondary alcohols distinguished them: nonacosan-10-ol from C. dupreziana (found chiefly in primitive plants) and nonacosan-5,10-diol from C. sempervirens (a novel long chain secondary diol in plant waxes).