HD 109749 is a binary star system about 206 light years away in the constellation of Centaurus. The pair have a combined apparent visual magnitude of 8.08, which is too faint to be visible to the naked eye. The primary component has a close orbiting exoplanet companion. The system is drifting closer with a heliocentric radial velocity of −13.2 km/s.
The primary component, HD 109749 A, is a G-type subgiant star with a spectral type of G3IV, indicating it is an evolved star with a luminosity higher than that of a main sequence star. It has a mass of and a radius of . The star is shining with a luminosity of and has an effective temperature of 5,860 K. Evolutionary models estimate an age of 4.1 billion years. HD 109749 A is chromospherically inactive and has a high metallicity, with an iron abundance 178% of Sun's.
The secondary, HD 109749 B, is a K-type main sequence star with an apparent magnitude of 10.3. It has a mass of about and is located at a separation of 8.4 arcseconds, which corresponds to a projected separation of 490 AU. This star has the same proper motion as the primary and seems to be at the same distance, confirming they form a physical binary system.
In 2005, an exoplanet was discovered around HD 109749 A. It was detected by the radial velocity method as part of the N2K Consortium. It is a hot Jupiter with a minimum mass of and a semimajor axis of 0.06 AU.