Disclosed herein is an injection needle assembly including a needle tube having a needle point to be made to puncture a skin； a needle hub including a first member which holds the needle tube, and a second member in which a discharge part of a syringe is to be fitted； and an elastic member disposed inside the second member to make liquid-tight close contact with an inner surface of the second member, the elastic member having an insertion hole in which the needle tube is inserted.
