The use of carbon fiber reinforced polymer (CFRP) composites becomes more attractive today in various industrial sectors such as aerospace, naval, and automotive. This is due to their high mechanical properties (strength, stiffness, light weight, etc.) and corrosion resistance. Machining processes such as trimming or drilling are frequently used to achieve dimensional tolerance and assembly requirements. However, a damage process involving matrix cracking, fiber fracture, and interlaminar delamination often occurs when machining these materials. In the current work, a numerical analysis has been used to identify the most significant machining factors and their interaction on the induced damage and cutting force. The orthogonal Design of Experiments (DoE) L27(313) of Taguchi has been applied to investigate the effect of the fiber orientation, the tool rake angle, the depth of cut, and the tool edge radius. The induced damage can strongly affect the surface roughness (surface quality of the workpieces) and considerably limits the use of these materials in many industrial applications. First of all, a coupled elastoplastic damage behavior law was adopted to simulate the permanent deformations caused by plasticity and to predict the degradation of mechanical properties due to the initiation of damage and its progression inside the composite structure. Satisfactory numerical results have been found and a good correlation has been obtained compared to experimental trends. The results reveal that the interaction between some factors could be neglected and the obtained responses are greatly influenced by the fiber orientation and the depth of cut rather than the tool rake angle and the tool edge radius.