The tissue distribution of the membrane receptor for the Sex Steroid Binding Protein (SBP) has been studied, either in estrogen/androgen dependent tissues and in tissues not strictly sex steroid dependent. A specific interaction of SBP with cell membranes has been observed to occur only in estrogen/androgen dependent tissues, some of them had been previously shown by our laboratory and by other authors to possess a specific receptor for the protein. Thus, the sex steroid dependence of the tissue is likely to be determinant for the expression of the membrane receptor for Sex Steroid Binding Protein.