Abstarct: The Zakeri manganese deposit is located 95 km southwest of Sabzevar, in Sabzevar structural-sedimentary subzone, and occurred within upper part of the late Cretaceous volcano-sedimentary sequence. This sequence hosts two mineralized horizons, the lower horizon has red tuff host rock, and the upper horizon is hosted by calcareous tuff and limestone. The Zakeri manganese ore deposit is situated in the upper horizon. At the Zakeri manganese deposit, baxsed on structure, texture, mineralogy and the relationship between ore with the host rocks; four ore facies can be recognized: vein-veinlets (stringer), brecciated, massive and bedded. The massive facies has the highest thickness and grade, and is minable. baxsed on electron probe micro analysis (EPMA), X-ray diffraction (XRD) and mineralogical studies, the deposit contains pyrolusite, psylomelane, hollandite, manganite, todorokite, rodochrosite and braunite ore minerals; and gangue minerals include calcite, chlorite, clay minerals and quartz. Dominant alterations at Zakeri manganese ore deposit include chloritic-carbonatic, argillic and silicic alterations. Argillic and silicic alterations are found mainly at the vein-veinlet and brecciated facies, enveloped by chloritic-carbonatic alteration. The ore textures at this deposit mainly include massive, banded, brecciated, disseminated, open-space filling, and replacement. The study of fossil remains at the microscopic sections shows that the deposit has been formed in a deep and calm environment. Igneous rocks in the region mainly have tholeiitic nature and have dacitic, andesitic and andesite-basaltic compositions, deposited at a back- arc settings. High ratios of Mn/Fe, La/Ce, U/Th, and Si/Al; low ratios of Co/Zn; and low content of Trace mextals, particularly Co, Cu and Ni; low contents of rare earth elements (REE) (especially Ce and Eu), and high values of SiO2, Mn and Fe in the ores, are evidences of manganese deposition from hydrothermal-exhalative fluids within a submarine environment. On the other hand, the role of hydrogenic processes in formation of this deposit has been insignificant The REE pattern of the studied ores shows a hydrothermal-exhalative origin and oxidized depositional marine environment for the deposit. The Zakeri deposit, baxsed on its comparison with different type of volcano- sedimentary manganes deposits, shows the most similarities to the Cuban- type deposits, in many characteristics such as geometry, host and associated rock- types, textures and structures, mineralogy, alteration and geochemistry.