15 Delphini (15 Del) is a star in the equatorial constellation Delphinus. It has an apparent magnitude of 5.99, allowing it to be faintly seen with the naked eye. The star is relatively close at a distance of 99 light years but is receding with a heliocentric radial velocity of .
15 Del has a stellar classification of F5 V, indicating that it is an ordinary F-type main-sequence star. It has 123% the mass of the Sun and a diameter of . It radiates at 3 times the luminosity of the Sun from its photosphere at an effective temperature of, giving a yellow-white hue. 15 Del has an iron abundance 74% that of the Sun and at an age of 1.21 billion years — spins leisurely with a projected rotational velocity of .
15 Delphini has 3 companions listed below. Components B and D have different proper motions compared to the host. However, C appears to have a common proper motion, suggesting physical relation, but its parallax indicates a further distance compared to 15 Delphini.
| B | 14.10 | 19 | 2013 | 52.1 | |
| C | 11.07 | 86 | 2020 | 105.5 | |
| D | 11.89 | 276 | 2020 | 189.6 |