Very little is known about the yield and chemical composition of the essential oil isolated from cones of Tetraclinis articulata (Vahl) Masters (Cupressaceae). In continuation of our on-going work devoted to the valorisation of medicinal and aromatic plants from Tlemcen Province (North-Western Algeria), cones have. been harvested in eight locations (coastal township and highlands) and 40 oil samples have been isolated by hydrodistillation. Six oil samples were analyzed by a combination of chromatographic [GC(Retention indices)] and spectroscopic techniques (GC-MS, "C NMR). Then, the remaining 34 oil samples. were analyzed by [GC(RI)] and 13C NMR and the 40 compositions were submitted to statistical analysis. Essential oil yields varied substantially from sample to sample (0.17 to 1.13%, w/w). The cone oils consisted mainly of monoterpenes, with α-pinene (47.1-73.6%) and limonene (6.5-21.9%) being the main components. (E)--Caryophyllene and germacrene D were the major sesquiterpenes. Diterpenes, (Z) and (E)-biformene were identified for the first time-in T. articulata essential oil. PCA analysis of the data allowed the distinction of two groups, the second group being sub-divided into two sub-groups. Groups and sub-groups were differentiated with respect to their contents of a-pinene and limonene and, to a lesser extent, of sesquiterpenes.