Background: Gitelman syndrome is a rare autosomal recessive disorder that typically presents with recurrent muscle cramps, carpopedal spasms, hypokalemic metabolic alkalosis, hypocalciuria and hypomagnesemia and high urine magnesium during adolescence. Mutation in the gene encoding for sodium chloride co-transporter in distal convoluted tubule causes electrolyte imbalance.Case presentation: We present a 10-year-old boy complaining of carpopedal spasms, tingling of fingers and facial parestesia for three years prior to his admission in endocrinology clinic of H. Ali-Asghar Pediatric Hospital. The patient had metabolic alkalosis, hypokalemia, hypocalciuria, increased urine fraction excretion of Mg, serum magnesium of 1.8 mg/dl, normal serum calcium and phosphorus and normal blood pressure. His clinical manifestations recovered after potassium and magnesium administration.Conclusion: A patient with Gitelman syndrome with normal serum Mg. is presented.