Adrenomedullin (AM) is a potent hypotensive peptide recently discovered from human pheochromocytoma tissue by its stimulating activity of platelet cAMP production. In this study, we have isolated the gene for human AM from a human genomic library and determined its structure. The genomic DNA of human AM consists of 4 exons and 3 introns, and the 5' flanking region contains TATA, CAAT and GC boxes. There are also multiple binding sites for activator protein-2 (AP-2) and a cAMP-regulated enhancer element. Southern blot analyses revealed that the AM gene is situated in a single locus of chromosome 11. These indicate that the human AM gene has components for its functional expression and that the expression may be subject to the activity of protein kinase C and the feedback from cAMP level.