The effect of several collectors and their dosage on the flotation characteristics of the synthetical fersmite at different pH values, the collecting strength and selectivity of several representative collectors were investigated. The experimental results indicate that diphosphonic acid is a good collector for fersmite and recovery of fersmite ranges from 83.27% to 85.10% when the pulp pH value is at 2.5-5.0 and the dosage is 20 mg/L. The rank sequence of selectivity for several collectors is as follows: diphosphonic acid > benzyl arsonic acid >α-styrolphosphonic acid>alkyl hydroximic acid (C7-9) > cyclic alkyl hydroximic acid. At the same time, Infrared Absorption Spectrum (IAS) and X-ray Photoelectron Spectroscopy (XPS) were used to detect and analyze the action mechanism of diphosphonic acid on fersmite. IAS results show that the characteristic absorption peak relating to PO as well as P-O vibration occurs between wave number 1 178 cm-1, 1 142 cm-1, 1 087 cm-1 and 934 cm-1, and diphosphonic acid is adsorbed on the surface of fersmite. XPS results indicate that the binding energy of P 2p peak of fersmite treated by diphosphonic acid is increased by 3.85 eV. It is proved that the adsorption is mainly chemical adsorption.