Abstarct: The granitoidic plutons of Aligoodarz (Darreh- Bagh and Gole-Zard) and Azna leucogranite outcropped in the western part of Lorestan Province and structural zone of Sanandag-Sirjan. The mentioned plutons with Middle Jurassic age are intruded into slate and phyllite of Hamedan. baxsed on exact field, petrographic and geochemistry investigations, the plutons belong to the S type granites and their compositions range from granodiorite to granite and leucogranite. The granodiorites constitute the main parts of Aligoodarz granitoides and include of plagioclase, quartz, alkali feldspar, (orthoclase and microcline) and biotite. Calcic cores of plagioclase (An91-84) with complicated zonation, small grained of biotite ± sillimanite assemblages, andalusite xenocrysts, crushed garnet with uniform composition (Alm70Py22Gro4Sps4) in core, cordierite, and inherited minerals of zircon, monazite and apatite as inclusions in biotite are the main residual minerals from partial melting of the source rocks and considered as restitic minerals. Granites are fine- grained and lighter in color compared with granodiorites.The leucogranitic rocks that characterized by white color and absent of opaque minerals occur as apophysis, dyke, vein and veinlet in Gole-zard and Darreh -Bagh plutons and cut granodiorite and granites. In Azna, leucogranites intruded as stock into regional mextamorphic rocks. Geochemical criteria also emphasis the petrographic evidences for presence of restites. Different degrees of separation of restites from initial melt composition appears to have been an effective differentiation process in the formation of more mafic rocks of the plutons but the relatively felsic was formed due to fractional crystallization. Considering the mineral assemblages in the Aligoodarz granitoides, occurrence of different restitic minerals and the average temperature of 780°C in agreement with the zircon saturation thermometry, it can be concluded that the studied plutons are formed by dehydration melting of biotite. Andalusite whit medium to high birefringence and the BSE images in which potassic feldspar and muscovite exist as pseudomorph of andalusite imply hydrothermal fluids during final stages of magma crystallization. Garnet in the Aligoodarz intrusive bodies is relatively euhedral but crushed and replaced by pennitized cordierite and biotite along fractures. The garnet contains constant composition and rich in almandine. The mineral zoning patterns of this mineral (decreasing #Mg and increase of Mn from the core to the periphery) show its restitic origin and has been subject to a process of regression. Enrichment of LILE (i. e., Rb, Th, K and U) and observed negative anomalies of Ba, Nb, Sr and Ti in the variation diagrams are similar to other S-type granites and pelitic sediments. Depletion of Ti and Nb are characteristics of magmas that formed in an environment of active continental margin. The studied granitoides are calc-alkaline, peraluminous and are S-type granites that are generated due to subduction of Neo-Tethys oceanic slab beneath Central Iran. Mafic dykes within the plutons are provided the required heat for melting of crustal rocks. The higher concentration of radioactive elements in mentioned granites, especially in Azna leucogranite suggest that crustal thickening and heat from the decay of radioactive elements could be another mechanism for increasing of geothermal gradient and melting process in Sanandaj-Sirjan mextamorphic belt. Existence of orthopyroxene (hypersthene) and sillimanite restites in the granodiorite indicates that these rocks are production of anatexis of psammite and pelites in temperature and pressure conditions of granulite facies.