THE PRESENT INVENTION IS MADE TO SECURELY POSITION A NEEDLE TIP AND A BLADE FACE OF A NEEDLE TUBE INSERTED INTO THE SKIN IN A PREDETERMINED SITE OF A LIVING BODY, SUCH AS THE UPPER LAYER OF SKIN. AN INJECTION NEEDLE ASSEMBLY INCLUDES A NEEDLE TUBE (2) HAVING A NEEDLE TIP CAPABLE OF PUNCTURING A LIVING BODY, A HUB (3) HOLDING THE NEEDLE TUBE, A STABILIZER (4), AND A GUIDE PORTION (7). THE STABILIZER (4) IS FORMED IN A TUBULAR SHAPE SURROUNDING THE CIRCUMFERENCE OF THE NEEDLE TUBE (2), AND AN END FACE (6B) IS PRESSED AGAINST THE SKIN, AND THEREBY A RAISED PORTION OF THE SKIN IS FORMED IN A TUBE HOLE (6A). THE GUIDE PORTION (7) IS ARRANGED ON THE STABILIZER (4), AND IS ADAPTED TO RECOGNIZE A PRESS-IN DISTANCE Y OF THE STABILIZER (4) TO THE SKIN.
