Watery diarrhoea, hypokalaemia and achlorhydria (WDHA) syndrome was caused by vasoactive intestinal polypeptide (VIP)-producing tumour. A 3-year-old Chinese girl with watery diarrhoea, abdominal distension and hypokalaemia due to a thoracic paraspinal VIP-secreting ganglioneuroma is reported. The girl coughed, fevering up to 39 degrees C after a flu-like episode. She had eight to ten abundant stools daily which is not improved by dietary treatment, resulting in an important weight loss. She weighed 6.8 kg (nl P50 at 6 months of age) and is 76 cm (nl P50 at 9 months of age) in height. Blood electrolytes showed 129 mmol/L sodium, 2.42 mmol/L potassium, 94 mmol/L chloride and 18.6 mmol/L bicarbonate; urinary catecholamines were normal. Computed tomography scan evidenced a left side paravertebral mass of 4 x 6 cm in the lower thoracic region leading to the blood determination of vasoactive intestinal polypeptide which amounted 830 pmol/L(normal < 25 pmol/L). Surgical removal showed a ganglioneuroma of 160 g and was associated with disappearance of the diarrhoea and normalization of VIP level below 20 pmol/L. Review of the 63 reported cases in children with WDHA showed that many of the cases presented with non-treatable watery diarrhoea, hypokalaemia. Achlorhydria is not necessarily part of the WDHA syndrome. The male to female ratio is 1:1.5. Ganglioneuroblastoma and ganglioneuroma are the commonest tumours. Location of the tumour is variable: abdomen, chest or neck. Abdominal distension, flushing, episodic hypertension and colonic dilatation, constipation and ataxia were the other associated features. Surgical resection is the treatment of choice of VIP-producing tumours.