Fructooligosaccharides are the most studied prebiotics. They are fructose oligomers linked to glucose and/or fructose molecules that contain up to ten sugar moieties. Fructooligosaccharides have both functional (physiologically beneficial to health) and technological properties. The aim of this article is to review published plant sources of different fructooligosaccharide types and production mechanisms, since the properties depend on the molecular structure. Fructooligosaccharide metabolizing enzymes, sources of specific fructooligosaccharide isomers and factors affecting their profiles reported in the plant species are also included.