Glucocorticoid receptor (GCR) protein stim- ulates transcription from a variety of cellular genes. We show here that GCR partially purified from rat liver binds specifi- cally to a site within the first intron of the human growth hor- mone (hGH) gene, =100 base pairs downstream from the start of hGH transcription. GCR binding is selectively inhibited by methylation of two short, symmetrically arranged clusters of guanine residues within this site. A cloned synthetic 24-base- pair deoxyoligonucleotide containing the predicted GCR bind- ing sequence interacts specifically with GCR. The hGH bind- ing site shares sequence homology with a GCR binding site upstream from the human metallothionein II gene and a subset of GCR binding sites from mouse mammary tumor virus. All of these binding sites for this eukaryotic transcriptional regu- latory protein show remarkable similarity in overall geometry to the binding sites for several prokaryotic transcriptional reg- ulatory proteins.