The New Caledonia ophiolite (Peridotite Nappe) consists primarily of harzburgites, locally overlain by mafic-ultramafic cumulates, and minor spinel and plagioclase lherzolites. In this study, a comprehensive geochemical data set (major and trace element, Sr-Nd-Pb isotopes) has been obtained on a new set of fresh harzburgites in order to track the processes recorded by this mantle section and its evolution.The studied harzburgites are low-strain tectonites showing porphyroclastic textures, locally grading into protomylonitic textures. They exhibit a refractory nature, as attested by the notable absence of primary clinopyroxene, very high Fo content of olivine (91-93 mol.％), high Mg# of orthopyroxene (0.91-0.93) and high Cr# of spinel (0.44-0.71). The harzburgites are characterised by remarkably low REE concentrations (<0.1 chondritic values) and displayU-shapedprofiles, with steeply sloping HREE (DyN/YbN = 0.07-0.16) and fractionated LREE-MREE segments (LaN/SmN = 2.1-8.3), in the range of mod fore-arc peridotites. Geochemical modelling shows that the HREE composition of the harzburgites can be reproduced by multi-stage melting including a first phase of melt depletion in dry conditions (15％fractional melting), followed by hydrous melting in a subduction zone setting (up to 15％-18％). However, melting models fail to explain the enrichments observed for some FME (i.e. Ba, Sr, Pb), LREE-MREE and Zr-Hf. These enrichments, coupled with the frequent occurrence of thin, undeformed films of Al2O3, and CaO-poor orthopyroxene (Al2O3 = 0.88-1.53 wt.％, CaO = 0.31-0.56 wt.％) and clinopyroxene with low Na2O (0.03-0.16 wt.％), Al2O3 (0.66-1.35 wt.％) and TiO2 (0.04-0.10 wt.％) contents, point to FME addition during fluid-assisted melting followed by late stage metasomatism most likely operated by subduction-related melts with a depleted trace element signature. Nd isotopic ratios range from unradiogenic to radiogenic (-0.80≤εNdi≤+13.32) and negatively corre-late with Sr isotopes (0.70257≤87Sr/86Sr≤0.70770). Pb isotopes cover a wide range, trending from DMM toward enriched, sediment-like, compositions. We interpret the geochemical signature displayed by the New Caledonia harzburgites as reflecting the evolution of a highly depleted fore-arc mantle wedge variably modified by different fluid and melt inputs during Eocene subduction.