Omicron Cephei is a binary star system in the northern constellation of Cepheus. Its name is a Bayer designation that is Latinized from ÿ Cephei, and abbreviated Omicron Cep or ÿ Cep. The combined apparent visual magnitude of the system is 4.75, which is bright enough to be visible to the naked eye as a point of light. Based on parallax measurements, it is located at a distance of from Earth.
This system consists of a less massive F-type main sequence star in orbit with a more massive G-type giant star. The pair was first determined to be binary by F. G. W. Struve in 1832. Since then, the secondary has been seen to revolve approximately 45 degrees around the primary. A number of orbits have been computed, with a 2003 study giving a period of approximately 1500 years.
There is a visual companion, CCDM J23186+6807C, to the binary star. It has an approximate apparent visual magnitude of 12.8 and is located approximately 45 arcseconds away from it.