Abstract: Late Cretaceous ophiolitic mélange complexes of the Izmir-Ankara-Erzincan Suture Zone (İAESZ) thatis the remnant of the northern branch of the Neotethys Ocean host numerous manganese oxide deposits in Turkey.These deposits are observed within the red-violet radiolarian chert blocks belonging to mélange units. Of thesemélange units, the Artova mélange is observed along the İAESZ in the northern part of the Kırşehir Massif, centralTurkey, is made up mainly of pelagic limestone, pillow basalt, radiolarian-chert blocks, highly alteredserpentinite. Mn-oxide mineralizations from Cihanpaşa (Yozgat, central Anatolia) region were analysed in orderto determine their depositional conditions, paleo-redox signatures, origin  source. These mineralizations arecomposed mainly of an alternation of radiolarian cherts mudstones that overlie altered pillow basalt in anoverturned fold. Based on petrographic studies, the mineral paragenesis of the manganese oxide mineralizations iscomprised predominantly of braunite, pyrolusite, pysilomelane quartz. Geochemically, high Mn/Fe (60.2), lowΣREE (15.75 ppm) Cu+Ni+Co (730 ppm), a negative Ce anomaly weakly negative Y/Y* anomaly (0.87) suggest that the Cihanpaşa manganese mineralizations formed in a submarine hydrothermal system. A negative Ce/Ce* anomaly (0.33), low Ceanom values (< − 0.54), redox-sensitive tracers [V/(V + Ni) = 0.43, Ni/Co = 0.51,V/Mo = 6.15)] indicate that the manganese mineralization was formed by a hydrothermal system in an oxygenatedmarine sedimentary environment. Further, a weakly positive negative Eu anomaly (0.84), high Lasn/Cesn (3.96),low Al/(Al + Fe) (0.34) ΣREE/Fe (30.7x10-4) ratios highlighted that the Cihanpaşa manganese mineralizationswere formed via impact of a low-T hydrothermal system, which is relatively close to the spreading ridge of the IzmirAnkara-Erzincan Ocean.