Abstract: The rupture and crushing of iron ore coal-containing mini-pellets will seriously affect the reduction of pellets in the dynamic drying.Effects of sodium additives on the heat strength of iron ore coal-containing mini-pellets in the dynamic drying were studied in order to improve heat strength of mini-pellets.The behaviors of heat strength of mini-pellets improved by sodium additive were investigated by using scanning electron microscopy to analyze inside of dynamic dry pellets and the influence of Zeta potential of coal-containing，iron ore and bentonite with sodium additives，then the mechanism of heat strength of pellets affected by sodium additives were expounded.The results showed that adding sodium additive can improve surface hydrophilicity of the particles,inhance the adhension role by bentonite,the ball inside will more dense,heat strength of dynamic were improved.With 3% additives，the dynamic drying degradation index of the dynamic drying pellet was 5.23%，and the compressive strength，the drop strength of dynamic drying mini-pellets and the quantity drop degradation index reached 10.88 N/P，3.1 times，and 3.26% respectively.Compared with the mini-pellets without additives，its index was improved significantly.

Key words: Mini-pellets, Sodium additives, Iron ore , Coal-containing, Heat strength