Abstract: Either β-adrenergic blockage orincreased activity of cyclic 3', 5' adenosine monophosphate phosph-odiesterase (cAMP-PDE)could theoretically decrease intracellular CAMP of patients with atopic dermatitis (AD).Humoral CAMP levels could refleet intracellular cAMP level in certain degree.Serum cANP of 57 AD patients were measured in the paper.The result showed that serum cAMP levels of AD patients were normal.