The results of major, trace, rare earth elements, Fe and Nd isotopic compositions of Xuanlong type iron ore deposit are reported. The characteristics demonstrate that the iron source of Xuanlong type iron ore deosit are from detrital input. Hematites show heavy Fe isotope enrichment relative to IRMM-014, which is different from the negative or zero iron isotopic composition of modern analogues formed by cyanobacteria. Therefore, the iron isotope data of hematite provide evidence for the presence of Fe-oxidizing bacteria. Geochemical features including the lack of Ce negative anomalies, enrichments of V, U, Mo, and the heavy Fe isotope enrichment of hematite samples implies the oxygen fugacity in the depositional environment was relatively low.