The elliptical vibration cutting (EVC) technique has been found to be a promising technique for ultraprecision machining of various materials. Researchers have proved that the EVC technique prevails over both conventional cutting and 1D vibration cutting techniques in most aspects in terms of cutting performances. However, during the EVC process, vibration marks or cusps are generated by the elliptical vibration locus and can result in an increase in the overall roughness of machined surface, which is undesirable for achieving high-quality mirror surface. Although researchers have developed a calculation method for the height of the cusps, only the effects of vibration frequency on surface generation were studied, and the effects of the other vibration and machining parameters have not been investigated in detail by previous researchers. Hence, in the present study, in order to deeply understand surface generation process along nominal cutting direction under the EVC technique, which is critical for its performance improvement and application, an experimental study comprising a series of grooving tests was carried out. The effects of nominal cutting speed on the surface generation at two different thrust-directional vibration amplitudes are investigated. Analysis is given for the comparison between the theoretical and experimental roughness values, showing that there exists a critical nominal cutting speed, below which the measured roughness value is quite small and the vibration marks are almost undetectable.