The most appreciated artichoke (Cynara cardunculus L. subsp. scolymus (L.) Hayek) cultivar in the central regions of Italy (Latium in particular) is the ’Romanesco’ type, because of its utilization in many typical regional recipes. In the last years, the in vitro production of C3, an early clone of artichoke ’Romanesco’ type, was mostly developed, with severe risks of genetic erosion of traditional local landraces. In this work, the biochemical characterization of eight clones of each landrace ’Castellammare’ and ’Campagnano’ was performed. In vitro micro-propagated clones from basal shoots collected in small traditional fields of Latium region were transferred, after acclimation, onto the experimental field located in Tarquinia (Viterbo) and then analysed for morpho-physiological traits. Secondary buds of each clone with an average weight of 200-220 g were analysed. On the edible part of the buds (hearts), the content of polyphenols and the fructan inulin, two important biochemical component that contribute to the nutritional properties of this vegetable (antioxidant and pre-biotic properties, respectively), were determined. In particular, chlorogenic acid, di-caffeoylquinic acids, apigenin-glycoside, simple sugars and inulin (expressed as fructose after hydrolysis) were evaluated by HPLC. The clones showed a good homogeneity in polyphenol and inulin content. Nevertheless, some of them showed significantly higher content of these components. Chlorogenic acid content ranged from about 300 to 530 mg 100g ^-1 f.w., while di-caffeoylquinic acids from 450 to about 800 mg 100g^-1 f.w. The apigenin-glycoside average content was 20 mg 100g^-1 f.w. For the inulin content, remarkable differences among clones were found in the early landrace ’Castellamare’, ranging from 1970 to 5250 mg 100g^-1 f.w.; while in the late landrace ’Campagnano’ the inulin content ranged from 1590 to 3900 mg 100g^-1 f.w.