Abstract: The accumulation of iron tailings containing rare earth and fluorite in Bayan Obo district not only harmed the environment, but also led to a huge waste of resources, among which iron minerals, rare earth, fluorite and other useful elements still have huge economic benefits.MLA (automatic mineral analyzer), SEM-EDX (energy spectrum-Scanning electron microscope), XRD (X-ray diffractometer) are used to study the element occurrence state, particle size distribution and distribution characteristics of MLA; meanwhile the chemical composition and mineral composition is detected by the optical microscope and chemical analysis.The results show that the content of iron in the tailings is 15.45%, in which hematite and magnetite is dominant, and magnetite mainly exists in the form of fine-grained and poor-continuous bodies, resulting the high content of iron in the tailings; the distribution of rare earth minerals is mainly composed of monazite (4.56%) and bastnaesite (6.33%), which is closely related to the distribution of fluorite.The research results provide an important basis for the comprehensive recovery and utilization of various useful minerals from the tailings containing rare earth and fluorite in Bayan Obo District.