tThe interaction mechanism of sodium diisobutyl dithiophosphinate (DTPINa) with chal-copyrite, pyrite, galena and sphalerite was investigated by single mineral flotationexperiment, adsorption measurement and FTIR spectrum analysis. Single mineral flotationexperiments showed that sodium diisobutyl dithiophosphinate exhibited a strong abilityto collect chalcopyrite and galena. For chalcopyrite and pyrite, the recovery of chalcopy-rite can reach 96.2% when the dosage is 12 mg/L and pH value is 8. In the same situation,the recovery of pyrite is as low as 13.5%. For galena and sphalerite, the recovery of galenareached 91.7% when the dosage was 50 mg/L at pH 11, and the recovery of sphalerite wasonly 16.9%. DTPINa adsorbed on chalcopyrite and galena surfaces are more than that onpyrite and sphalerite surfaces. The adsorption capacity of DTPINa on the minerals surfaceis proportional to its dosage. The FTIR spectrum analysis results showed that the adsorp-tion of DTPINa on sulfide minerals surface is chemical and S atoms in P S and P S mayhave taken part in the reaction. The natural ores experiments also confirmed the excellentperformance of sodium diisobutyl dithiophosphinate.