Omicron Andromedae (ο And, ο Andromedae) is a star system in the constellation Andromeda. It is approximately 692 light years from Earth.
Omicron Andromedae is a binary star, whose two components are both spectroscopic binaries themselves, making a four-star system. The system as a whole is classified as a blue-white B-type giant with a mean combined apparent magnitude of +3.62.
The separation of the two brightest components, ο Andromedae A and ο Andromedae B, is 0.34 arcseconds. They have an orbital period of 68.6 years. A is separated from its spectroscopic companion by 0.05 arcseconds. A is a Gamma Cassiopeiae type variable star and the system's brightness varies from magnitude +3.58 to +3.78. This, in turn, has made determination the orbital period of A's spectroscopic binary difficult. B's spectroscopic companion was discovered in 1989, and that binary has a period of 33.01 years.
This star system has a peculiar velocity of 34.5 ± 5.9 km/s.