Sanukitoids (high Mg-granitoids) are a group of distinctive Neoarchean granitoids, which differ in chemical composition from the voluminous tonalite-trondhjemite-granodiorite (TTG) suite. Shirey and Hanson (1984) first introduced the term sanukitoid to refer to mantle-derived rocks, which resemble high-Mg andesites, known as sanukites in the Miocene Setouchi belt of Japan. Stern et al.(1989) defined sanukitoid geochemistry as SiO2= 55–60%, MgO> 6%, Mg#> 60, Sr> 600–1800 ppm, Ba> 600–1800 ppm, Cr> 100 ppm, Ni> 100 ppm and LREE enriched compared to HREE. The term sanukitoid series has been introduced for granitoids with relatively high Mg#, MgO, Sr, Ba, Cr and Ni at any given silica level (Lobach-Zhuchenko et al., 2005). Sanukitoids composition shows some similarities to adakites (Martin, 1999) and to recently described Neoarchean Closepet-granites (Moyen et al., 2001). Interpretation of the geochemistry of sanukitoids is controversial. High Mg#, MgO, Ni and Cr implies that sanukitoids are mantle-derived rocks, but high Sr, Ba and LREE suggest crustal origin (Stern & Hanson, 1991). These aspects of sanukitoid geochemistry have been explained with a two-stage process, which includes Archean subduction. In the first stage, melts and/or fluids derived from a subducting basaltic slab enriched the overlying mantle wedge with Sr, Ba and LREE. Later melting of the enriched mantle generated sanukitoid magmas (Stern & Hanson, 1991; Kovalenko et al., 2005). Pb isotopic studies indicate that subducted sediments may also have played an important role in the sanukitoid petrogenesis (Halla, 2005). Sanukitoids might thus be the first sign of existence of an enriched mantle wedge and the beginning of the modern style of plate tectonics (Martin & Moyen, 2005).