<p>A medical syringe comprising a cylindrical connection supporting member increasing the holding force of a lure inserted into a connection target. The connection supporting member is formed to be slid along the lure or a syringe body part in a state of being movable between a first position near a tip of the lure and a second position away from a tip of the lure. The syringe is characterized in that , when the connection supporting member is moved to the second position, the tip of the lure is exposed.</p>