The white-winged black tyrant (Knipolegus aterrimus) is a species of bird in the family Tyrannidae. It has often included the Sao Francisco black tyrant (K. franciscanus) as a subspecies. It is found in Argentina, Bolivia, Chile, Paraguay, Peru, and Uruguay. Its natural habitats are subtropical or tropical moist montane forests, subtropical or tropical moist shrubland, and heavily degraded former forest.