The present invention provides a method for adding a little fresh and fragrant raw material into a sterilized green tea beverage container. The preparation method of green tea extract comprises the following steps: collecting vapour containing raw tea aroma components generated by tea through a raw tea steam heat process step, cooling collected vapour, and obtaining an extract containing the raw tea aroma components, then performing steam distillation of obtained green tea through a conventional step, and obtaining an extract extracted from the vapour extracting tea residue employing water after steam distillation, and obtaining an extract extracted by water and mixing the extract containing the raw tea aroma components, the extract extracted by vapour and the extract extracted by water.