The relationship between simultaneous serum electrolyte and blood glucose levels was studied in 119 moderately or severely dehydrated children with acute infectious gastroenteritis. Their ages ranged between two months to fifteen years. A positive correlation was found between blood glucose and serum sodium levels in the children with serum bicarbonate values below 15 mmol/L. This correlation is more prominent in cases of severe metabolic acidosis with serum bicarbonate values less than 10 mmol/L. No correlation was found between blood glucose, serum potassium and chloride levels. Our results show that a positive correlation between blood glucose and serum sodium levels is present only in cases with metabolic acidosis, which is contrary to classical knowledge.