Abstract: A precision filter for accomplishing filtering of precision of submicron order. A filter element of the filter consists of a plurality of superposed disc-shaped annular support members for filter membranes. Each support member has a radially outwardly extending intermediate section located between an annular boss section and an outer frame section. The intermediate section is formed on its upper and lower sides with a plurality of gently winding elongate ridges and largely winding elongate ridges. Each largely winding elongate ridge extends from the boss section to the outer frame section, but each gently winding elongate ridge located between the two largely winding elongate ridges is separate from the boss section thereby to form two elongate winding grooves which are joined and continuous to a central opening of the boss section.