Through a simple operation made possible by adoption of a simple structure, this drug delivery device (1) connects an syringe barrel (6) and a drug container (2) by means of a closed system, and delivers a drug between the syringe barrel (6) and drug container (2) through said closed system. This drug delivery device (1) includes a first member (8) connected to the drug container (2) on the side of a stopper (4), and a second member (30) connected at one end to the first member (8) and connected at the other end to the syringe barrel (6). The first member (8) and the second member (30) are connected by a fitting mechanism. A second hollow needle member (34) provided on the second member (30) faces towards the first member (8), and the tip portion (36) and the base portion (38) are fixed. The first member (8) has a first hollow needle member (12). The first member (8) and the second member (30) each have an elastic member (18 and 40), and the first member (8) and the second member (30) are connected in a state in which the elastic members (18, 40) are in contact. In said state of contact, the second hollow needle member (34) passes through the elastic members (18, 40) and is inserted into the first hollow needle member (12). This drug delivery device (1) delivers the drug between the syringe barrel (6) and the drug container (2) through the first hollow needle member (12) and the second hollow needle member (34).Selon linvention, par lintermédiaire dune opération simple rendue possible par adoption dune structure simple, le dispositif dadministration de médicament (1) de la présente invention relie un corps de seringue (6) et un récipient de médicament (2) au moyen dun système fermé, et administre un médicament entre le corps de seringue (6) et le récipient de médicament (2) par lintermédiaire dudit système fermé. Le dispositif dadministration de médicament (1) de la présente invention comprend un premier élément (8) relié au récipient de médicament (2) sur le côté d
