The jet mask electrolytic discharge technique was proposed for machining workpieces due to the uncertainty of the discharge breakdown during electrolytic discharge machining,resulting in inconsistent shape and poor quality of the machined workpieces.By analysing the structure of the jet,studying the decay law of the circular turbulent jet flow along the axis and calculating the initial section length,the nozzle and fixture were designed and fabricated.A jet electrolytic machining setup was built and a blue oil mask was prepared on a stainless steel workpiece to experimentally study the effect of machining distance on the shape of the crater.The experiments show that the jet ejected by the nozzle with a conical converging structure has good mechanical properties and can be used to machine the workpiece using the initial section of the jet.A blue oil mask of 50 μm thickness with a skeletonised pattern is applied to the workpiece,which effectively improves the material removal in a fixed domain.The maximum material removal rate is achieved at a machining distance of 2 mm.