Abstarct: Diane copper deposit is located in North Central zone of the volcanic arc Toruod- Chahshirin in Semnan province, 90 km South of Damghan city. The deposit consists of extracting three zones including: zones 1, 2 and 3 filled empty places of Eocene volcanic rocks. On the baxse of field study, optical microscopy and geochemical analyses (XRD, XRF, ICP, EPMA): the ore body of Diane copper consists of andesite, trachyandesite, basalt, trachybasalt, trachyte, tuff and agglomerate, which are porphyry, porphyry microlitic flow in textures. The volcanic rocks also show amygdaloidal and pillow structures indicating that they are formed in submarine environment. They are alkaline to calc-alkaline in nature and are plotted in fields of island arcs and active continental margin and show the subduction process with crustal contamination. Moreover, LREE enrichment in compare with HREE are a character of those magma formed in subduction zones. According to correlation coefficients of exist elements, the most important associated elements with Diane deposit are zinc, gold, and molybdenum. The most important ore-forming minerals are malachite, chalcocite, chrysocolla and filled some fractures, breccia and cavities of the volcanic rocks. Finally, with studying the all mineralogy features, texture and geochemistry and comparison with similar deposits in the Iran (Chah Gole, Kalate Mehran, Chah Musa, … ) and world (Chile, Canada and USA), it is concluded that the Diane copper is an vein copper deposits.