This study aims to investigate the effect of a cationic-anionic mixed collector (dodecyltrimethyl ammo-nium bromide/sodium oleate (DTAB/NaOL) on the selective separation of apatite, dolomite, and potas-sium feldspar. Herein, several experimental methods, including flotation experiments, zeta-potential detection, microcalorimetry detection, XPS analysis and FTIR measurements, were used. The flotation tests showed that dolomite and potassium feldspar can be successfully removed from apatite simultane-ously when the molar ratio of DTAB to NaOL was 2:1 with pH 4.5. Zeta-potential and microcalorimetry detection suggested that NaOL and DTAB were adsorbed on the surface of dolomite and potassium feld-spar respectively, and part of NaOL and DTAB formed co-adsorption on the surface of potassium feldspar to enhance the floatability of potassium feldspar. The XPS and FTIR spectra analysis demonstrated that the cationic collector, DTAB, was first adsorbed on the surface of potassium feldspar through electrostatic attraction in the DTAB/NaOL mixture system. Subsequently, the anionic NaOL collector and cationic DTAB collector form an electron neutralisation complex, thereby resulting in co-adsorption on the surface of potassium feldspar. NaOL was chemically reacted and adsorbed on dolomite surface, but almost no col-lector was adsorbed on apatite surface. Finally, the adsorption models of different collectors on mineral surface were obtained.& COPY; 2023 Published by Elsevier B.V. on behalf of China University of Mining & Technology. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).