Drug injection syringe

A drug injection syringe comprising:

• an injection needle assembly comprising:
• an injection needle,
• a needle hub supporting the injection needle,
• an elastic body disposed on the needle hub, wherein the injection needle is disposed in the elastic body, and
• a fitting sleeve accommodating the needle hub and the elastic body, and including a fitting hole formed in a female taper shape having a diameter that decreases toward a needle tip;
• and
• a syringe body comprising:
• an outer tube configured to contain a drug sealed by a gasket disposed in the outer tube, and
• a drug discharge tube provided on a front end side of the outer tube, wherein the drug discharge tube has a male taper shape configured to fit in the female taper shape of the fitting sleeve,
• wherein the syringe body is configured to be attached to the injection needle assembly by pushing the drug discharge tube into the fitting hole by press fitting,
• wherein the elastic body comprises a pocket that opens to a contact surface configured to make contact with a distal end of the drug discharge tube, and
• wherein the elastic body is configured to couple the drug discharge tube and the injection needle in a liquid-tight manner by compressively deforming, due to the press fitting, at a protruding portion disposed on a periphery of the pocket and stretching against an inner wall of the fitting hole.