Hypertension in obese children may require a different diagnostic and treatment approach from that for children with secondary hypertension, yet there is neither consensus nor a clear guideline. The aim of this study was to assess how obese children with hypertension are currently diagnosed and treated by paediatric nephrologists, what obstacles exist and what can be improved. In the period May–November 2014, an online questionnaire was sent to all members of the European Society for Paediatric Nephrology (n = 2148). Questions focused on current practices and obstacles regarding screening, diagnosis and treatment of hypertension in obese children. A total of 214 paediatric nephrologists responded. Although nearly 100 % agreed that screening of obese children for hypertension is indicated, it was current practice in only 56 % of participating countries; 88 % of respondents diagnosed hypertension with 24-h ambulatory blood pressure measurement. Diagnostics used to rule out causes or consequences of hypertension varied among the respondents; they included, in particular, the use of serum renin/aldosterone, urine sodium/potassium, and dimercaptosuccinic acid scan. Concerning treatment, 45 % of respondents preferred to start treatment with a lifestyle program, 2 % with antihypertensive medication, and 40 % with both. For 73 % of respondents, angiotensin-converting enzyme-inhibitors or angiotensin receptor blockers were the drugs of first choice. The findings of this study emphasize the urgent need for an international guideline for screening, diagnosis and treatment of hypertension in obese children.