The synthesis and the first X-ray structural characterization of a selenenyl selenocyanate, [o-(2,6-diisopropylphenyliminomethinyl)phenyl]selenenyl selenocyanate (DiPhSeSeCN), with a stable Se–Se bond are described. The isolation of stable DiPhSeSeCN, both in the solid state and in solution, is facilitated by strong intramolecular Se⋯N interaction. The compound DiPhSeSeCN, an example of unsymmetrical diselenide, did not exhibit any glutathione peroxidase-like activity. The reaction of DiPhSeSeCN with thiophenol afforded (3H-benzo[c][1,2]diselenol-3-yl)(phenyl)sulfane.