Gitelman syndrome(GS) is a renal tubular disorder of the thiazide-sensitive Na-Cl cotransporter (NCCT), which is located in the distal tubule of the loop of Henle. GS is an autosomal recessive disease of renal tubulopathy, primarily characterized by hypokalemic metabolic alkalosis with significant hypomagnesemia, low urinary calcium, secondary aldosteronism and normal blood pressure. GS is distinguished from Bartter syndrome, which is associated with mutations of several genes, by the presence of hypomagnesemia and hypocalciuria. In most of the patients with GS, the disease manifests with transient episodes of muscular weakness and tetany in the adult period, but, often, is asymptomatic. Both hypokalemia and hypomagnesemia were reported to cause impaired glucose tolerance and/or insulin resistance, but it is unclear whether impaired glucose tolerance and/or insulin resistance are common in GS patients. We have experienced one patient whose initial complaint was paresthesia of hand and feet, and abnormal glucose metabolism, abnormal insulin sensitivity who had hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria.