Selective flocculation desliming reverse flotation is suitable for processing fine and micro-fine disseminated high-silica, low-grade hematite ores. First, the ore is finely ground to liberate the iron minerals from the gangue. Then, a dispersant (water glass, sodium hydroxide, sodium hexametaphosphate, etc.) is added to the pulp to disperse the iron minerals and adjust the pH to 9-10. Next, a flocculant (starch, sodium humate, hydrolyzed polyacrylamide, etc.) is added to flocculate and settle the iron mineral particles, removing the suspended gangue slime. This flocculation process can generally be repeated several times. The iron concentrate obtained after selective flocculation often does not meet quality requirements and needs further processing using cationic or anionic collector reverse flotation to finally obtain a qualified concentrate.