Abstract: A water purifier that assures easier change of a used filter comprises a base, at least one filter replaceably attached to the base and including a first end with a first fluid port and a second end with a second fluid port, a first connector supporting the first end of the filter in a separable manner and including a connector port connected to the first fluid port of the filter, a second connector spaced apart from the first connector to accomodate the filter therebetween and including a bore aligned with the second fluid port of the filter, a spool fitted into the bore of the second connector for movement between an extended position allowing fluid flow and a contracted position preventing fluid flow, and a spool actuator for slidingly moving the spool between the extended position and the contracted position.