Résumé : Aim Reports suggest that 10% of hospitalised children in Europe are undernourished. We investigated whether nutritional screening tools (NST) were used in Belgian secondary-level hospitals, examined strategies for detecting undernutrition and identified barriers preventing the systematic management of undernutrition. Methods A nationwide questionnaire-based survey of paediatric departments in Belgian secondary-level hospitals was carried out from September 2013 to February 2014. Respondents were dived into French-speaking (Walloon + Brussels) and Dutch-speaking (Flemish) departments. Results We received replies from 71 of the 97 (73.2%) departments. Half of the departments - 39.5% Flemish speaking and 71.4% Walloon speaking - carried out nutritional screening. Undernutrition was identified by measuring weight and length or height (92.7% of cases), clinical appraisal (74.7%), mid-upper arm circumference and/or skin fold thickness (19.7%). There was no protocol for undernutrition in many Flemish (60.5%)- and Walloon (28.6%)-speaking departments. Reasons given for not screening were as follows: lack of training (46.9%), ignorance of NST (42.2%) and lack of time (29.7%). Conclusion Half of the paediatric departments in Belgian secondary-level hospitals did not carry out nutritional screening, and differences in current practices and attitudes may be due to cultural and/or educational differences.