The　effects　of　carbonate　minerals　(dolomite　and　siderite)　on　the　flotation　of　hematite　using　sodium　oleate　as　a　collector　were　investigated　through　flotation　tests,　supplemented　by　dissolution　measurements,　solution　chemistry　calculations,　zeta-potential　measurements,　Fourier　transform　infrared　(FTIR)　spectroscopic　studies,　and　X-ray　photoelectron　spectroscopy　(XPS)　analyses.　The　results　of　flotation　tests　show　that　the　presence　of　siderite　or　dolomite　reduced　the　recovery　of　hematite　and　that　the　inhibiting　effects　of　dolomite　were　stronger.　Dissolution　measurements,　solution　chemistry　calculations,　and　flotation　tests　confirmed　that　both　the　cations　(Ca2+　and　Mg2+)　and　CO3　(2-)　ions　dissolved　from　dolomite　depressed　hematite　flotation,　whereas　only　the　CO3　(2-)　ions　dissolved　from　siderite　were　responsible　for　hematite　depression.　The　zeta-potential,　FTIR　spectroscopic,　and　XPS　analyses　indicated　that　Ca2+,　Mg2+,　and　CO3　(2-)　(HCO3　(-))　could　adsorb　onto　the　hematite　surface,　thereby　hindering　the　adsorption　of　sodium　oleate,　which　was　the　main　reason　for　the　inhibiting　effects　of　carbonate　minerals　on　hematite　flotation.