Abstract: The effect of the regulators on the flotation of quartz and silicate minerals is concerned when it is added before or after the collectors. The flotation test of quartz and feldspar pure mineral was carried out by changing the addition order of inorganic, organic regulators and collectors on the premise of 70 mg/L dodecyl amine hydrochloride. The test results showed that sodium hexametaphosphate or starch added first can make a better effect on quartz flotation. For feldspar, sodium hexametaphosphate added first could produce a better inhibitory effect, and starch added later could produce a better inhibitory effect than added before. The infrared spectra showed that there were electrostatic adsorption and hydrogen bonding between dodecylamine hydrochloride and both minerals. Sodium hexametaphosphate was only adsorbed on feldspar, and starch had no adsorption on quartz and feldspar.