The present invention relates to a method of making a prosthetic valve that can take a first form wherein the valve is open and a second form wherein the valve is closed, the valve comprising a leaflet assembly having at least two leaflets attached to a supporting element, the leaflets having a free margin that can move between a first position wherein the valve takes the first form and a second position wherein the valve takes the second form, the method comprising providing a single piece of fabric, made by weaving warp and fill threads into a seamless tubular woven fabric having at least one stabilized edge, and forming the fabric into a leaflet assembly having an inner layer forming the leaflets with the stabilized edge forming the free margin, and an outer layer forming the supporting element. With this method a prosthetic valve can be made from a single piece of fabric made by tubular weaving techniques, and resulting in a valve with high reliability and durability. The invention also relates to a method of making a leaflet assembly, and to a leaflet assembly and a prosthetic valve obtainable by said methods.