The present disclosure provides a carbonation preservation device that attaches to the mouth of an open container holding carbonated liquid. More specifically, the present invention relates to a device for preventing loss of carbonation from a carbonated liquid stored within a container by purging the trapped air above the remaining liquid within the container and replacing it with carbon dioxide or mixture of gases. When in place, the carbonation preservation device purges the air and other gases from the volume above the remaining carbonated liquid and fills the volume with a gas, such as carbon dioxide, or a mixture of gases, in order to pressurize the container and prevent the escape of carbon dioxide from the remaining carbonated liquid in the container.