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The studied area (Galali- Varmaqan) located at the northern part of the Sanandaj- Sirjan zone, south of the Qorveh city. The granitic rocks are dominated by quartz, alkalifeldspar and plagioclase. Amphibole and biotite are the most important mafic minerals, apatite, sphene, zircon and Fe- oxides are the accessories. The Galai- Varmaqan granitoids show geochemical characteristics of metaluminous A-type granites with mainly shoshonitic and high- K calc- alkaline affinity. Based on geotectonic diagrams, these rocks are mostly clusterred at the volcanic arc granites (VAG) and within plate granites (WPG) fields which points to their formation in a post- orogenic magmatic system. LILEs and HFSEs enrichment indicates the existence of a crustal source for the studied granites and formation of the parent magma at the stability field of plagioclase in the lack of garnet. In this study, we suggest that the A-type granites have been formed by partial melting of lower crust charnokitic rocks. The A-type granites are related to extensional magmatism of the Neo- Tethys oceanic crust beneath the Central Iranian microcontinent, due to roll- back of subducting slab. Thus, change of tectonic regime from compressional to tensional in the late- Jurassic to early- Cretaceous time (probably in a pull-apart basin tectonic setting), is suggested for the formation of A-type granites in this region of the Sanandaj- Sirjan zone. [ABSTRACT FROM AUTHOR]