High entropy alloys belong to the emerging multi-component alloys, which have a wide range of applications in aerospace and micro components. In order to investigate the micro-milling performance of FeCoNiCrMnAlx (x=0, 0.6, 1) high-entropy alloys, the effects of different process parameters such as spindle speed, feed per tooth, and depth of milling on their micro-milling force, cutting specific energy, and surface roughness were investigated by using a one-way experimental method. The results show that: Al1 has the largest milling force and the worst surface quality; Al0 has better machinability due to lower milling force, specific energy of cutting and surface roughness; for each alloy, the micro-milling force and surface roughness increase and then decrease with the spindle speed and feed per tooth, and increase with the increase of milling depth; in order to reduce the alloy's milling force and surface roughness, it is possible to appropriately In order to reduce the milling force and surface roughness of the alloy, the spindle speed and feed per tooth can be increased and the milling depth can be reduced.