Hasankeyf is an ancient city located on the shores of the Tigris River in Batman Province, southeast Turkey. The town and some of its surrounding villages will be soon submerged, due to the construction of Ilısu Dam, which will force the residents to move to new settlements. The aim of the present study was to collect and record the traditional knowledge regarding the indigenous wild plants that will be submerged by this flooding. The study was carried out between March 2017 and April 2019. Interviews were conducted with 72 women and 53 men in the town center and 22 rural settlements, with a focus on the five villages that are due to be submerged. Information about a total of 86 wild edible plants belonging to 32 families was recorded. Interviewees reported that these were used as green vegetables (45 taxa), ripe fruits and seeds (25 taxa), seasoning and preservatives (16 taxa), beverages (nine taxa), and children’s snacks (seven taxa). In addition, the data were analyzed on the basis of the cultural importance index to determine the cultural significance of these wild edible plants and the informants’ knowledge about them. Culturally, the most significant species included <em>Mentha longifolia</em>, <em>Polygonum cognatum</em>, <em>Rosa canina</em>, <em>Chenopodium album</em>, <em>Urtica dioica</em>, <em>Amaranthus retroflexus</em>, and <em>Malva neglecta</em>. In addition, the data were compared with relevant data in the ethnobotanical literature of Turkey and its neighboring countries. Several uses mentioned here are documented here for the first time. Our research highlights the importance of wild edible plants in the daily lives of inhabitants and their potential for economic use. The present study also provides information for future archaeobotanical studies in this region.