Qatar-3 is a 12th magnitude star located in the northern constellation Andromeda. It is host to a transiting planet.^[2] With a radial velocity of 10.99 km/s, it is drifting away from the Solar System, and is currently located 2,400 light years away based on its annual parallax.

This star is a hot yellow dwarf with 14.5% more mass than the Sun, and 27.2% larger. It has a luminosity of almost two times that of the Sun, and has effective temperature of 5,991 K, which gives it a yellow hue. Qatar-3 is also a metal poor star that has a similar metallicity to the Sun, and has a rapid rotation rate of 10.4 km/s. This means it takes Qatar-3 6.31 days to complete a full rotation, while the Sun takes almost a month to rotate.

In 2016, the Qatar Exoplanet Survey discovered a planet around Qatar-3, Qatar-4, and Qatar-5, which was led by an international team in Qatar. Qatar-3b is a massive planet, with 4.31 times the mass of Jupiter, and has a similar radius to the latter. With a density of 4.0 g/cm³, this is one of the densest planets discovered. With an effective temperature of 1,681 K, it is a scorching planet.^[4]

Qatar-3b is a hot Jupiter.^[5] It orbits its star every 2.5 days. It was discovered in 2016 by the Qatar Exoplanet Survey(QES).^[6][7] This planet was discovered by QES along with Qatar-4b and Qatar-5b. The light curves of the planet's respective host stars have been observed as well during the survey, along with their stellar properties.^[8][7]