The present invention relates to a filtering syringe, and more particularly, to an apparatus obtained by improving a syringe provided with a filter means for filtering foreign substances such as glass fragments of an ampoule, so as to prevent an injection needle or an injection flow passage from being contaminated with the foreign substances while allowing a liquid medicine to be smoothly sucked with a smaller force. The filtering syringe is configured such that the injection needle or the injection flow passage is isolated from the suction flow passage which is upstream of the filter means and in which the foreign substances may remain together with the liquid medicine, thereby allowing the liquid medicine to be sucked with a force less than that required for a conventional syringe and thus maximizing users convenience and marketability of the syringe.