Human movements via migrations facilitate the transport of plants and knowledge. Migrations were always present in our human history, but conflicts and environmental changes are contributing to the increase in people’s movements to and from different parts of the world. In this literature review, our focus is on the ethnobotany of food plants and migrations, and the adaptations following this process. We analyzed 58 studies dealing with human migrations and food plants, including both internal migrations and international ones, over a wide period from several centuries to the present but with the predominance of migrations since the second half of the twentieth century. Most studies reported migrations between countries or regions (80%) in which people search for better economic opportunities. Other reasons for migrations were refugees, mandatory displacements, and slavery. The studies included cultivated plants, gathered plants (foraged), and food plants purchased on markets or obtained via exchanges or importation. We discuss the identitarian role of food plants in the processes of maintenance, abandonment, replacement, and incorporation of plants; although the evidences of abandonment are the most difficult to track. After the migration, the maintenance of a food identity will depend on several variables, including how important it is to keep a distinct identity, the plant resources available, the people’s agency of the plant resources, and also the reasons for each migratory movement. Finally, we discuss the implications of this ethnobotanical knowledge and practices related to food plants for sustainability.