An integrated puncture needle adapter for connecting a drug storage container having a drug storage space to store a drug and a liquid storage container having a liquid storage space to store a liquid for dissolving or diluting the drug, the integrated puncture needle adapter comprising: a puncture needle having a needle tip capable of puncturing a living body at a distal end of the puncture needle and an internal passage opening at both ends of the puncture needle; a needle hub which supports the puncture needle so that the needle tip of the puncture needle protrudes from a distal side of the needle hub; a first connecting part which is provided on a proximal side of the needle hub, and which connects the liquid storage space and the internal passage in a liquid-tight manner by a connection with the liquid storage container; a tubular fixing part which is provided on the distal side of the needle hub, and which fixes the needle hub in a liquid-tight manner by use of an adhesive or by welding, or by a combination of them; a tubular puncture needle accommodating part which is provided on a distal side of the tubular fixing part integrally with the tubular fixing part, and wherein the tubular puncture needle accommodating part has therein an accommodating space for accommodating the puncture needle; a second connecting part which is provided on a distal side of the puncture needle accommodating part so as to communicate with the accommodating space, and wherein the second connecting part connects the drug storage space and the internal passage in a liquid-tight manner by a connection with the drug storage container; and a separable part formed between the tubular fixing part and the puncture needle accommodating part, wherein the separable part is capable of separating a distal part at a distal side relative to the separable part from a proximal part at a proximal side relative to the separable part, and the puncture needle is exposed when separated. a puncture needle having a needle tip capable of puncturing a living body at a distal end of the puncture needle and an internal passage opening at both ends of the puncture needle; a needle hub which supports the puncture needle so that the needle tip of the puncture needle protrudes from a distal side of the needle hub; a first connecting part which is provided on a proximal side of the needle hub, and which connects the liquid storage space and the internal passage in a liquid-tight manner by a connection with the liquid storage container; a tubular fixing part which is provided on the distal side of the needle hub, and which fixes the needle hub in a liquid-tight manner by use of an adhesive or by welding, or by a combination of them; a tubular puncture needle accommodating part which is provided on a distal side of the tubular fixing part integrally with the tubular fixing part, and wherein the tubular puncture needle accommodating part has therein an accommodating space for accommodating the puncture needle; a second connecting part which is provided on a distal side of the puncture needle accommodating part so as to communicate with the accommodating space, and wherein the second connecting part connects the drug storage space and the internal passage in a liquid-tight manner by a connection with the drug storage container; and a separable part formed between the tubular fixing part and the puncture needle accommodating part, wherein the separable part is capable of separating a distal part at a distal side relative to the separable part from a proximal part at a proximal side relative to the separable part, and the puncture needle is exposed when separated.