The effect of power output form on the morphology of diamond wire is studied.In the experiment,ϕ0.18 mm copper plating high carbon steel wire is used as the baseline,while the size of diamond particle is 30-40 μm,surface of which has been chemically plated with nickel phosphorus alloy at weight increase of 30%.The output forms of the power are DC output,single pulse output and double pulse output.The aggregation of diamond particles on the wire is reduced gradually when the duty ratio reduces from 0.8 to 0.2,while the optimum duty ratio is 0.6.The aggregation phenomenon of diamond particles is gradually reduced when the opening ratio of the positive pulse of double pulse output reduces from 8 to 2,while the optimum opening ratio is 6and diamond particles are well distributed.Theoretical analysis shows that the negative pulse of the double pulse output has desorption effect on the agglomeration diamond,so it can effectively restrain the agglomeration phenomenon.At the same time,too strong desorption effect will reduce the amount of sand.