Minimal quantity lubrication (MQL) machining has been accepted as a successful semi-dry application because of its environmentally friendly characteristics and satisfactory performance in practical machining operations. However, seldom investigation has been done in MQL machining of titanium alloy at high cutting speeds. In this paper, high speed milling experiments with MQL9 ml/h of oil in a flow of compressed air have been carried out for a widely used titanium alloy Ti6Al4V. Uncoated cemented carbide inserts have been applied in the experiments. Within the range of cutting speeds employed (190 m/min~300 m/min), the cutting performance of MQL has been investigated when peripheral milling the titanium alloy Ti6Al4V in terms of cutting forces, surface roughness, tool life and wear mechanism. The results show that, compared to dry machining, MQL machining brings about a significant reduction in cutting forces and surface roughness, and it also gives rise to a notably prolonged tool life.