An injection preparation comprising: an aqueous composition containing the following (i) to (iii); and a container which encloses the aqueous composition, wherein the concentration of oxygen in gas within the container which encloses the aqueous composition is less than or equal to 0.2 volume%, or wherein the ratio of the number of oxygen molecules with respect to the number of pemetrexed molecules in the injection preparation is less than or equal to 0.0025: (i) pemetrexed or a salt thereof; (ii) at least one antioxidant agent which is selected from the group consisting of ascorbic acid, an ascorbic acid derivative, and salts thereof, and the content of which is 0.0001 mass% to 0.5 mass% with respect to the total mass of the aqueous composition in terms of ascorbic acid, wherein the ascorbic acid derivative is ascorbyl monostearate, ascorbyl monopalmitate, ascorbyl monoisopalmitate, ascorbyl monooleate, ascorbyl distearate, ascorbyl dipalmitate, ascorbic acid monophosphate ester, ascorbic acid diphosphate ester, ascorbic acid triphosphate ester, ascorbic acid monoglucoside, ascorbic acid diglucoside, ascorbic acid ethyl ether or ascorbic acid methyl ether; and (iii) an aqueous solvent of greater than or equal to 50 mass% with respect to the total mass of the aqueous composition. an aqueous composition containing the following (i) to (iii); and a container which encloses the aqueous composition, wherein the concentration of oxygen in gas within the container which encloses the aqueous composition is less than or equal to 0.2 volume%, or wherein the ratio of the number of oxygen molecules with respect to the number of pemetrexed molecules in the injection preparation is less than or equal to 0.0025: (i) pemetrexed or a salt thereof; (ii) at least one antioxidant agent which is selected from the group consisting of ascorbic acid, an ascorbic acid derivative, and salts thereof, and the content of which is 0.0001 mass% to 0.5 mass% with respect to the total mass of the aqueous composition in terms of ascorbic acid, wherein the ascorbic acid derivative is ascorbyl monostearate, ascorbyl monopalmitate, ascorbyl monoisopalmitate, ascorbyl monooleate, ascorbyl distearate, ascorbyl dipalmitate, ascorbic acid monophosphate ester, ascorbic acid diphosphate ester, ascorbic acid triphosphate ester, ascorbic acid monoglucoside, ascorbic acid diglucoside, ascorbic acid ethyl ether or ascorbic acid methyl ether; and (iii) an aqueous solvent of greater than or equal to 50 mass% with respect to the total mass of the aqueous composition. (i) pemetrexed or a salt thereof; (ii) at least one antioxidant agent which is selected from the group consisting of ascorbic acid, an ascorbic acid derivative, and salts thereof, and the content of which is 0.0001 mass% to 0.5 mass% with respect to the total mass of the aqueous composition in terms of ascorbic acid, wherein the ascorbic acid derivative is ascorbyl monostearate, ascorbyl monopalmitate, ascorbyl monoisopalmitate, ascorbyl monooleate, ascorbyl distearate, ascorbyl dipalmitate, ascorbic acid monophosphate ester, ascorbic acid diphosphate ester, ascorbic acid triphosphate ester, ascorbic acid monoglucoside, ascorbic acid diglucoside, ascorbic acid ethyl ether or ascorbic acid methyl ether; and (iii) an aqueous solvent of greater than or equal to 50 mass% with respect to the total mass of the aqueous composition.