Provided is a double container which comprises a relatively rigid outer container and a flexible inner container disposed inside the outer container and capacity-variable in response to an amount of a content thereof The double container is configured to contain, particularly, a high-viscosity liquid, e.g., a liquid having a viscosity of 1000 to 100,000 mPa/s, and to be easily produced by a forming technique having no significant difference from conventional techniques, wherein the double container for a high-viscosity liquid is capable of containing the content without causing oxidation thereof, while maintaining the outer container in its original shape or dimensions, and discharging the content by squeezing the outer container, irrespective of a level of a remaining amount of the content.