Abstarct: Manganese mineralizations at southwest of Sabzevar occurred in the Sabzevar structural subzone, within the Late Cretaceous volcano-sedimentary sequence . These mineralizations baxsed on stratigraphic position, relative age and type of country rocks lie within two main horizons: a) Horizons I: This horizon which hosts the Nodeh, Ferizi and Goft manganese deposits, occurs in the lower part of the Late Cretaceous sequence. The host rock of these deposits is red tuff. b) Horizons II: This horizon involving the Zakeri and Cheshmeh Sefid deposits, occurred in the upper part of the Late Cretaceouse sequence. The host rocks are marly tuff and carbonatic tuff. Manganese oxide mineralization occurs as sheet-like and tabular ore bodies within six subhorizons in the Nudeh deposit and within two subhorizons in the Ferizi and Goft deposits. baxsed on mineralogical, textural, structural and relationships between the ores and the host rocks, three ore facies can be distinguished: 1) massive ore facies, 2) bedded ore facies, and 3) disseminated- brecciated (stringer) ore facies. Mineralogicaly, these facieses contain pyrolusite, psilomelane, Braunite and Mnganite. Wall rock alterations in the Nudeh deposit are dominated by chloritization and argillitization. Argillic alteration is observed immediately bellow the massive ore facies, surrounded by chloritic alteration.In the Goft and Ferizi deposit, only chloritization is observed. Chloritization in the deposits is more intense in the footwall than the hangingwall. baxsed on geochemical studies, high amount of Mn/Fe, La/Ce, U/Th and Si/Al ratio, low amount of Co/Zn ratio, trace mextals and especialy Co, Cu and Ni, low amounts of rare earth elements (REE), specially Sm, Ce and Eu and high amounts of Fe, Mn, and SiO2 are of precipitation of Mn from evidences of hydrothermal- exhalative fluids within a marine environment. And, role of hydrogenous processes involved in the genesis of this deposit is minimal. Also, REE patterns indicate hydrothermal-exhalative origin and oxidation conditions for the Marine environment for the deposit. Electron probe micro analysis (EPMA) study on the manganese minerals of the massive and bedded ore facieses show a lateral zoning for Fe and Mn from massive to bedded facies. The most important characteristics of mineralization at the Nudeh deposit and its comparision with different types of volcano-sedimentary Mn deposits show the most similarities with the Cuban-type deposits.