A method of preparing an enteric hard capsule, the method comprising: dissolving an enteric base material, a capsule forming aid, and a neutralizing agent in water at room temperature to prepare an aqueous composition, wherein the enteric base material comprises at least one compound selected from the group consisting of hydroxypropyl methyl cellulose phthalate (HPMCP) and hydroxypropyl methyl cellulose acetate succinate (HPMCAS), the capsule forming aid comprises cellulose ether, the cellulose ether comprises at least one compound selected from the group consisting of hydroxypropyl methylcellulose (HPMC) and methylcellulose, and the neutralizing agent comprises an alkaline material; heating the aqueous composition to a first temperature that is higher than a gelation start temperature of the aqueous composition by 1 °C to 20°C; cooling the heated aqueous composition to a second temperature that is lower than the gelation start temperature by 15 °C to 40°C; immersing a mold pin heated to a third temperature that is higher than the gelation start temperature by 10°C to 40 °C into the aqueous composition; removing the mold pin from the aqueous composition to obtain a film coated on the mold pin; maintaining the film on the mold pin at a fourth temperature that is higher than the gelation start temperature for a first time period to fix the film onto the mold pin, wherein the fourth temperature is from 60°C to 80 °C, and the first time period is from 1 minute to 15 minutes; and drying the fixed film at a fifth temperature for a second time period to obtain a capsule shell, wherein the fifth temperature is from 20°C to 40°C, and the second time period is from 30 minutes to 60 minutes. dissolving an enteric base material, a capsule forming aid, and a neutralizing agent in water at room temperature to prepare an aqueous composition, wherein the enteric base material comprises at least one compound selected from the group consisting of hydroxypropyl methyl cellulose phthalate (HPMCP) and hydroxypropyl methyl cellulose acetate succinate (HPMCAS), the capsule forming aid comprises cellulose ether, the cellulose ether comprises at least one compound selected from the group consisting of hydroxypropyl methylcellulose (HPMC) and methylcellulose, and the neutralizing agent comprises an alkaline material; heating the aqueous composition to a first temperature that is higher than a gelation start temperature of the aqueous composition by 1 °C to 20°C; cooling the heated aqueous composition to a second temperature that is lower than the gelation start temperature by 15 °C to 40°C; immersing a mold pin heated to a third temperature that is higher than the gelation start temperature by 10°C to 40 °C into the aqueous composition; removing the mold pin from the aqueous composition to obtain a film coated on the mold pin; maintaining the film on the mold pin at a fourth temperature that is higher than the gelation start temperature for a first time period to fix the film onto the mold pin, wherein the fourth temperature is from 60°C to 80 °C, and the first time period is from 1 minute to 15 minutes; and drying the fixed film at a fifth temperature for a second time period to obtain a capsule shell, wherein the fifth temperature is from 20°C to 40°C, and the second time period is from 30 minutes to 60 minutes.