The present invention provides a drug injection apparatus in which it is possible to press a flexible drug container to discharge a drug from an injection needle while stably holding the drug injection apparatus in a state where the injection needle has been stuck into a living body. The drug injection apparatus of the present invention includes a drug container, a needle tube, a needle-holding portion, and a drug container mount. The needle tube has a first needle tip and a second needle tip, and the central portion of the needle tube is held by the needle-holding portion. The second needle tip projects from the drug container mount. The drug container has a container body, a seal member and a protective plate. The container body has a contact portion to be penetrated by the second needle tip and a pressing portion that faces the contact portion, wherein the pressing portion is to be pressed toward the side of the contact portion so as to deform. The seal member is attached to a portion of the contact portion to be penetrated by the second needle tip, so that the seal member closely contacts the circumferential surface of the needle tube in a liquid-tight manner. The protective plate is provided to avoid the pressing portion from being penetrated by the second needle tip inserted into the container body.
