We report the discovery of a giant planet candidate transiting a white dwarf star. The planet candidate orbits its host star every 1.4 days, is about the size of Jupiter, and has a mass less than about 14 MJup. The planet candidate orbits close enough to the white dwarf that it must have formed farther out to avoid destruction when the host star evolved into a red giant. Previously, the presence of asteroids and planets near white dwarfs has been inferred from observations of debris disks, transiting material, and refractory materials in the stellar spectra, but it was unclear whether any planets could make the journey while avoiding tidal disruption. This new discovery demonstrates that low-mass objects can survive migration into close orbits around white dwarfs.