Machine tools as a main device in manufacturing and production lines are widely used nearly in all branches of industries. Precision continuation of these systems with times and against inspected shocks is necessary and very important. Turning as a main kind and high usage machine tool is used in many industrial parts production, especially those with rounded sections. Spindle, tailstock and bed in machine tools play engraving role in dimensional accuracy. In this paper the vibration effects on the tailstock of a turning machine during its operation, is analyzed. For this purpose, a LZ330 VS machine from Weiler Co. in Germany is modeled with Solid Works software. This model with IGES format is transferred to ANSYS 5.4 analytical software. In this area, the model is analyzed via modal and transient dynamic analysis. The results show that, the more tailstock’s sleeve length, the less critical frequency amount.