The serum amylase level is widely used as a screening test for acute pancreatitis and rises also in a wide variety of diseases involving the pancreas, salivary glands, intestines, liver, genitourinary tract, and lung, in metabolic aberrations such as diabetic ketoacidosis, and even during normal pregnancy. Although it is commonly assumed that the diseased organ is releasing amylase into the serum, in many conditions the precise relationship between the hyperamylasemia and the condition is not clear. Serum amylase is abnormally elevated in more than 60% of patients with diabetic ketoacidosis, but increased pancreatic enzyme activity, even in combination with abdominal pain, should not be diagnosed as acute pancreatitis. In nonketotic hyperosmolar syndrome, elevated serum amylase level without pancreatitis has not been reported. Nonketotic hyperosmolar syndrome is usually a complcation of type 2 DM and characterized by severe hyperosmolarity (serum osmolality> or =320 mOsm/L), hyperglycemia (serum glucose> or = 600 mg/dL) and dehydration. We experienced two cases of nonketotic hyperosmolar syndrome with elevated serum amylase. Serum amylase level was 1556 U/L in first case, 229 U/L in second case. Two patients did not complain of abdominal pain, nausea, vomiting and abdomen CT with enhancement showed the normal pancreases.