Prevalence of dysfunctional eating behavior was investigated in 311 adult persons with mental retardation living in the West Coast of Norway. Reports from a questionnaire filled out by health workers were used as observational data. The main finding was that 64.3% of the clients showed indices of dysfunctional eating behavior. The five most frequent dysfunctional behaviors was eating too fast (27.7%) followed by bolting one's food (25.1%), refusal of food (19.9%), excessive eating (18.3%) and non co-operative during mealtime (17.0%). In 50% of the cases, one or more eating dysfunctions was present every day and the intensity of the behavior was regarded as high or very high in 26.2% of the cases. It is suggested that more studies are needed to single out treatment approaches to eating dysfunctions in adult persons as has been done on food refusal in children.