This study assessed the clinical indicators and severity of dysphagia in a representative sample of children with severe generalized cerebral palsy and intellectual disability. A total of 166 children (85 males, 81 females) with Gross Motor Function Classification System Level IV or V and IQ < 55 were recruited from 54 daycare centres. Mean age was 9 years 4 months (range 2y 1mo-19y 1mo). Clinically apparent presence and severity of dysphagia were assessed with a standardized mealtime observation, the Dysphagia Disorders Survey (DDS), and a dysphagia severity scale. Additional measures were parental report on feeding problems and mealtime duration. Of all 166 participating children, 1% had no dysphagia, 8% mild dysphagia, 76% moderate to severe dysphagia, and 15% profound dysphagia (receiving nil by mouth), resulting in a prevalence of dysphagia of 99%. Dysphagia was positively related to severity of motor impairment, and, surprisingly, to a higher weight for height. Low frequency of parent-reported feeding problems indicated that actual severity of dysphagia tended to be underestimated by parents. Proactive identification of dysphagia is warranted in this population, and feasible using a structured mealtime observation. Children with problems in the pharyngeal and esophageal phases, apparent on the DDS, should be referred for appropriate clinical evaluation of swallowing function.