As one kind of high strength and thermal resistant nickel-based alloys, Inconel 718 has been used extensively in aerospace industries. To satisfy the instant requirements of higher material removal rate and good surface integrity from engineering practice, high speed machining of Inconel 718 is an inevitable trend. The influences of cutting speed on surface integrity were investigated through the experimental study with high-speed milling Inconel 718 using Sialon ceramic tool. The results showed that higher cutting speed could exploit to give excellent surface integrity. The best surface integrity was obtained in the investigation at the highest cutting speed of 1400m/min in the applied cutting speed range.