Disclosed herein are a filter assembly for a syringe, a syringe including the same and a ringer assembly, which are able to filter and collect any impurity mixed with a medicinal fluid when the medicinal fluid is sucked from an ample into the syringe and allow to inject only the medicinal fluid while blocking the flow of the impurity when administrating the medicinal fluid in the syringe into a human body. The filter assembly for a syringe according to the present invention may include a needle holder configured to fix an injection needle at a front end thereof, wherein a neck part of a cylinder is inserted into a rear end thereof and a filter unit which includes a support member which is formed in a single tube shape having a hollow part, wherein an outer side surface contacts close with the surrounding of the inner surface of the needle holder corresponding to the outer side surface is formed at a rear end in the longitudinal direction, wherein the support member is formed of a head part which forms one or more through holes passing through in the forward and backward directions and formed along the surrounding between the hollow part and the outer edge, and forms a hollow part communicating with the hollow part of the head part, and an extension tube which extends backward from the center of the back surface of the head part a valve member which is formed in a horn shape, wherein a front end of the valve member forms a skirt part shaped to cover a circumferential portion of the through hole, and a rear end thereof which extends backward from the hollow circumferential portion of the back surface of the skirt part reaches the hollow rear end of the support member or is inserted in a protrusion shape and includes an extension part which forms a cutting line in the center of the rear end thereof and a filter wherein a front opening formed in a pocket shape is engaged in a shape covering the side wall of the extension tube.
