Abstract: Disclosed herein is a filter assembly for water purifiers. The filter assembly includes a head having an inlet duct, a control valve, and an outlet duct. A circular cap is provided on the lower portion of the head, and has cylindrical space. A filter cap is mounted to the circular cap. A filter cartridge has a filtering part which is provided with a filter to purify water. A plurality of fastening holes is formed in the outer circumference of the circular cap, and has a step. Locking parts are disposed in the fastening holes to lock the filter cartridge. An elastic member surrounds the circular cap and the outer surfaces of the supports parts, thus elastically supporting the locking parts to the fastening holes. The filter cap has on the outer circumference of the upper portion thereof a plurality of fastening holes into which the locking parts are fitted.