Aim: To develop and validate a screening tool for feeding/swallowing difficulties and/or undernutrition in children with cerebral palsy (CP). Method: This cross-sectional, observational study included 89 children with CP (63 males, 26 females; median age 6y 0mo; interquartile range 4y 0mo–8y 11mo), across all Gross Motor Function Classification System levels. Children with feeding tubes were excluded. Children were classified as well-nourished or moderately to severely undernourished, using the paediatric Subjective Global Nutrition Assessment. Eating and drinking abilities were classified using the Eating and Drinking Ability Classification System (EDACS) from mealtime observation and videofluoroscopic swallow studies when indicated. Parents/caregivers answered 33 screening questions regarding their child's feeding/swallowing abilities and nutritional status. The diagnostic ability of each question for identifying children with feeding/swallowing difficulties and undernutrition was calculated and the combination of questions with the highest sensitivity and specificity identified. Results: Feeding difficulties impacted on swallow safety in 26 children (29%) and 26 children (29%) were moderately or severely undernourished. The 4-item final tool had high sensitivity and specificity for identifying children with feeding/swallowing difficulties (81% and 79% respectively) and undernutrition (72% and 75% respectively). The tool successfully identified 100 per cent of children with severe undernutrition and 100 per cent of those classified as EDACS level IV or V. Interpretation: Screening for feeding/swallowing difficulties and undernutrition will enable early identification, assessment, and management for those children in need. What this paper adds: A screening tool with high sensitivities and specificities for identifying children with feeding/swallowing difficulties and undernutrition. The tool identified 100 per cent of children with severe undernutrition. The tool identified 100 per cent of children in Eating and Drinking Ability Classification System levels IV or V.