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In order to improve the performance of magnesia dolomite materials, magnesium dolomite refractory materials whose iron oxide content (mass fraction) of 0, 0.5%, 1.0%, 1.5%, respectively, were prepared from natural dolomite, high silicon magnesite, silica and iron oxide powder by two-stage calcination and slaking process. The influence of iron oxide content on the physical properties, hydration resistance and coatability adherence of the samples was investigated. The phase composition and microstructure of the specimens were characterized. The results showed that, as the iron oxide content increased, the room temperature flexural strength and the room temperature compressive strength increased, the high temperature flexural strength and the adherence strength decreased, and the retention rate of the thermal shock strength of the sample first increased and then decreased. With the iron oxide content increasing to 1.5%, the hydration weight gain rate of the sample decreased to 0. 12%, and the hydration resistance improved. According to the XRD spectrum analysis, the main crystal phases of the sample were periclase, dicalcium silicate and tricalcium silicate. With the increase of iron oxide content, the diffraction peaks of C2S and C3S became stronger and the peak shapes were sharp. It showed that iron oxide could promote the growth of C2S and C3S crystals and increase the density of the sample. [ABSTRACT FROM AUTHOR]