A container which accommodates a drug and is sealable, the container comprising: a container stopper part including at least one filling groove formed in order to inject a drug; and a container body including an opening into which the container stopper part is inserted and which is sealable, wherein the filling groove is formed in an outer wall surface of the container stopper part in a longitudinal direction in which the container stopper part is inserted thereinto and forms a passage which is formed between the outer wall surface of the container stopper part and an inner wall surface of the container body and through which the drug is injectable, wherein the filling groove is formed in the outer wall surface of the container stopper part to have a semicircular shape in the longitudinal direction in which the container stopper part is inserted thereinto, and characterized in that a groove is formed in the outer wall surface of the container stopper part between a first seating portion and a second seating portion; a protrusion is formed on the inner wall surface of the container body; when the container stopper part is inserted into the opening of the container body and an end of the first seating portion of the container stopper part is caught on and in contact with the protrusion, the drug is injectable; and when the container stopper part is press-inserted into the opening of the container body, the end of the first seating portion of the container stopper part passes the protrusion, and the protrusion is seated on the groove formed between the first seating portion and the second seating portion, the container stopper part seals the opening of the container body. a container stopper part including at least one filling groove formed in order to inject a drug; and a container body including an opening into which the container stopper part is inserted and which is sealable, wherein the filling groove is formed in an outer wall surface of the container stopper part in a longitudinal direction in which the container stopper part is inserted thereinto and forms a passage which is formed between the outer wall surface of the container stopper part and an inner wall surface of the container body and through which the drug is injectable, wherein the filling groove is formed in the outer wall surface of the container stopper part to have a semicircular shape in the longitudinal direction in which the container stopper part is inserted thereinto, and characterized in that a groove is formed in the outer wall surface of the container stopper part between a first seating portion and a second seating portion; a protrusion is formed on the inner wall surface of the container body; when the container stopper part is inserted into the opening of the container body and an end of the first seating portion of the container stopper part is caught on and in contact with the protrusion, the drug is injectable; and when the container stopper part is press-inserted into the opening of the container body, the end of the first seating portion of the container stopper part passes the protrusion, and the protrusion is seated on the groove formed between the first seating portion and the second seating portion, the container stopper part seals the opening of the container body.