The purpose of this study was to investigate the preparation and cooking processes used to prepare Eungi in cookbooks published from the 1700s to the 1900s. ‘Eungi’ is a thin gruel made of starch powder. Fourteen historical cookbooks were included and investigated for the preparation of ingredients and processing methods. Fourteen types of eungi were identified. Arrowroot eui and kuseonwangdogo eui were found in 『Kyuhapchongseo』 written in the early 1800s, and many types of eungi (i.e. job’s tears eungi, arrowroot eungi, sorghum eungi, lotus root eungi) were mentioned in 『Kunhakhoedeung』, but unfortunately, ingredients and cooking methods were not included. ‘Eungi’ was made by boiling starch powder prepared using the ‘subi method’, that is, dried after grinding main ingredients such as job’s tears using a millstone followed by soaking and settling. Eungi boiled with water or omija water were seasoned with the sugar or honey, and salt. These eungis were used for stomach complaints and hangovers and to promote longevity.