We report here the first published case of a pediatric patient with Gitelman's syndrome (GS) in whom hypokalemia-associated rhabdomyolysis developed. A 13-year-old girl was admitted with weakness of the extremities, walking difficulty and calf pain. Laboratory data showed a serum potassium level of 2.1 mmol/l and a serum creatinine phosphokinase level of 1,248 IU/l plus myoglobinemia. The presence of normomagnesemia was the basis for a genetic analysis of the thiazide-sensitive sodium chloride cotransporter gene, which revealed compound heterozygous mutations in this gene. Prompt fluid expansion and potassium supplementation led to regression of the muscle symptoms. Hypokalemia can be a rare cause of rhabdomyolysis in patients with GS, even in childhood. We emphasize that genetic analysis is advisable to determine whether the suspicion of GS is warranted.