Belt finishing has been tested successfully as a complementary process to hard turning. This technology improves the surface texture and generates compressive residual stress. However, the mechanisms and characteristics of this new process have not yet been fully explained. This article provides a comprehensive characterization of cutting mechanisms generated by belt finishing. First, an analytical analysis based on cutting forces is developed. Then, the macroscopic specific energy is dissociated into a cutting specific energy responsible of shearing and ploughing mechanisms and a sliding specific energy due to adhesion. It has been demonstrated that cutting is more predominant than sliding in belt finishing process. The omnipresence of cutting demonstrates the effectiveness and the profitability of belt finishing operation.