In this work, the ball-end mill machining has been analyzed and a model based on mechanics of metal cutting is developed. This model is used for prediction of the cutting forces in ball-end milling from fundamental data. The cutting edge in this model is considered as a series of infinitesimal elements and the oblique cutting process with these elements has been analyzed as orthogonal cutting process. Cutting forces result from the summation of cutting forces on these elements. The results have been compared with the experiments on machining 1045 steel and Al4Ti6V and show relatively good agreements.