Calcite and scheelite have the same active particles and similar crystal structure, and the flotation behavior is similar. In this paper, a kind of organic ellagic acid (EA) with low molecular weight and high stability was studied as a new environmental inhibitor of low dose calcite. The microflotation test results show that when the dosage of EA is 8 mg/L and NaOL is 30 mg/L, the recovery rate of calcite is 6.22% and the recovery rate of scheelite is 89.35%, which has obvious inhibition effect on calcite. By zeta potential evaluation and Fourier transform, the surface of calcite galena reduces its hydrophobicity and hinders the adsorption of collector. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) analysis show that EA occurs mainly through the interaction of -OH and C=O hydrophilic groups with calcium atoms on the surface of calcite, forming Ca-O-C bonds leading to stable adsorption. New, efficient and environmentally friendly organic inhibitors are designed to selectively change the surface properties of calcite and enhance the flotation efficiency of scheelite and calcite.