Field fertilizer experiments were conducted to identify the most effective dosage of ZnSO4 and Rosabor applied to Robusta coffee grown on Ferralsols of DakLak Province. All of experiment plots were applied with 260kg N + 95kg P2O5 + 240kg K2O and 10 tons of manure (every two years). The results showed that ZnSO4 0,4 percent + Rosabor 0,25 percent plots with 5 times/year (twice in the dry season and thrice in the rainy season) increased the content of nitrogen, potassium, zinc and boron in leaves. Application of ZnSO4 and Rosabor also exerted positive effect on the growth and development, increased reserve branch length by 17 percent and reduced the ratio of fresh/dry'pean by 4 percent.Highest yield of coffee beans per ha could attain 3.97 tons with VND 71.78 million annual profit.