In Sahand area, northern part of Urmia-Dokhtar Magmatic Arc (UDMA) there are some high silica adakitic domes with rhyolite, dacite, trachy-dacite, trachy-andesite and andesite composition belonging to Late Eocene-Pliocene, the Eocene volcano-sedimentary series and in some cases the Oligocene-Miocene sedimentary rocks. They enclose some fragments of these rocks as xenoliths. The most abundant minerals in these rocks are plagioclase and amph-ibole with various textures such as felsitic porphyric, microlitic porphyric, sieve, flowage and glomeroporphyric. The parent magma of these rocks is calc-alkaline and per-aluminous in nature which is characteristics of the arc volcanism. These rocks fell in to the field of high-silica adakites (HAS) in classification diagrams. Enrichment in light rare earth elements (LREEs) and large ion lithophile elements (LILEs) and depletion in heavy rare earth elements (HREEs) are obvious in their MORB, primitive mantle and chondrite-normalized spider diagrams. Strong depletion in HFSEs including Nb, Ti and P which is signature of arc volcanism, can be observed in these rocks. According to the petrogenetic diagrams, the parent magma of the rocks studied was generated by partial melting of an eclogitic or garnet amphibolitic source derived from metamorphism of the Neotethyan subducted oceanic slab underbeneath the Central Iranian zone. Also, the magma has been subjected to assimilation, fractional crystallization (AFC) and crustal contamination during ascend to higher levels and emplacement. The presence of the corrosion and chemical disequilibrium of the phenocrysts and their sieve textures in these rocks support the occurrence of these processes.