Abstract: A Cu-Ni(PGE) ore-bearing mafic-ultramafic rocks belt is exposed in central Inner Mongolia, EW extending about 400km long and 30km wide. This belt is located on both sides of the fracture of the North China Craton and stretches across two tectonic units: Baoyintu magmatic arc and Bayan Obo marginal rift. As a remote geographical position, the research is relatively weak in this area. In recent years, many Cu-Ni(PGE) deposits (ore occurrences) including Ebutu, Dabuxun, Tepogeritu, Wengeng, Kebu, Huanghuatan and Xiaonanshan have been discovered in this belt, raising the concern of geologists gradually. Based on the systematical summary and analysis of geochemical data, the author mainly carried out the research on geochemical characteristics of the Cu-Ni(PGE) ore-bearing mafic-ultramafic rocks belt. The ore-bearing intrusions are formed in the range of 314—269Ma, indicating that they should be the products in late Variscan era. Most of rocks belong to tholeiitic series, and parts of rocks are calc-alkaline series in petrochemical composition. Gabbros and pyroxenites show two types of REE patterns: relatively flat REE patterns with inconspicuous fractionation of LREE and HREE, and rightward oblique linear REE patterns with LREE enrichment in relative to HREE(La_N/Yb_N is 1.49 to 20.08), and exhibit positive Eu anomaly or negative anomaly(δEu is 0.56 to 1.66); Pyroxene peridotites also show LREE-enrichment(La_N/Yb_N is 5.56 to 13.57) and HREE relatively flat, right-inclined REE distribution pattern, and display negative Eu anomaly(δEu is 0.57 to 0.83). Overall, all rocks show rightward oriented linear REE patterns with LREE enrichment in relative to HREE and exhibit a regular ΣREE decrease from gabbros to pyroxene peridotites, and are characterized by negative HFSE (Nb, Ta, Zr) anomalies. According to these geochemical characteristics, it may be inferred that all of the ore-bearing intrusions in this belt may come from the same source of magma, and magmatic assimilation occurs in the evolution. With high MgO and low-alkaline, the intrusions show high Mg^# value and high m/f ratios, which indicates good prospecting potential.