DP Leo is a bright A-type star (about 0.69 solar masses, 13,500 K), 306 light-years from Earth. DP Leo b is a 6.05-Jupiter-mass companion, with an orbital period of 28.0 years, at 8.190 AU from its star, on an eccentric orbit (e ≈ 0.39), discovered in 2009 via eclipse timing variations. DP Leo adds another data point to the growing catalogue of planetary systems whose masses, orbits, and host-star properties constrain models of planet formation. The planet's marked eccentricity suggests past scattering events or perturbations from unseen companions.