Abstract: Three styles of hydroentangling nozzles are designed depending on the requirement in hydroentangling process,that is,cone-capillary nozzle,streamline nozzle and capillary-cone nozzle.A CFD technique is employed to simulate the formation of the water-jets discharged from these nozzles,and the effect of nozzle geometry on water-jet breakup length is analyzed depending on the simulation result.The experiments indicate that the cone-capillary nozzle geometry makes the water jet discharged from the nozzle fogged easily on the water jet surface,and the breakup length of the water jet is shorter;the streamline nozzle geometry makes the disturbance of the nozzle wall to the water flow inside this nozzle decreased,and the breakup length of the water jet is longer;and the capillary-cone nozzle geometry is optimum for water jet to keep collimated and coherent,and the breakup length of the water jet is the longest.