In this paper were determined the effects of cutting speed, cutting tool and feed rate on cutting forces and surface roughness based on Taguchi experimental design. The effects of machining parameters were investigated using Taguchi L-18 orthogonal array. Three different cutting cemented carbide tools were used in experiments as K313, KCU10 and KCU25. Main cutting force Fz was considered to be cutting force as a criterion. The experimental design described herein was used to develop a main cutting force and surface roughness prediction model using analysis of Taguchi. Optimal cutting conditions were determined using the signal-to-noise (SN) ratio which was calculated for average surface roughness and cutting force according to the "the smaller is better" approach. Using results of analysis of variance (ANOVA) and SN ratio, effects of parameters on both average surface roughness and cutting forces were statistically investigated. In the experiments, depending on the tool material, lowest main cutting force 370 N at 75 m/min with KCU 25 and lowest average surface roughness (0.424 mu m) at 60 m/min with KCU 25 cemented carbide tool was found. It was found the effect of feed rate 0.198%) and cutting tool (0.06%) has higher effect on the cutting force and the feed rate (18.82%). The cutting speed (17.31%) has shown higher effect on average surface roughness. In the cutting force turning tests KCU25 and in the surface roughness turning tests, K313 cutting tool has shown better performance than the other cutting tools.