The Harris's Hawk or Harris Hawk, Parabuteo unicinctus, formerly known as the Bay-winged Hawk or Dusky Hawk, is a medium-large bird of prey which breeds from the southwestern USA south to Chile and central Argentina.

It is the only member of the genus Parabuteo. The name is derived from the Greek para, meaning beside or near, and the Latin buteo, referring to a kind of hawk; uni meaning once; and cinctus meaning girdled, referring to the white band at the base of the tail.

Individuals range in length from 46 to 76 cm and generally have a wingspan of 1.1m. In the United States, the average weight for males is about 710g, while the female average is 1020g. This is a sexual dimorphism of about 40%, with the female being larger than the male. They have dark brown plumage with chestnut shoulders, wing linings, and thighs, white on the base a tip of the tail, long, yellow legs and a yellow cere. The vocalizations of the Harris's hawk are very harsh sounds.

The juveniles are similar to the adults but are more streaked, and when in flight the undersides of the wings are buff-colored with brown streaking.

The bird lives in sparse woodland and semi-desert, as well as marshes.

The diet consists of small creatures including birds, lizards, mammals, and large insects. Because it will hunt in groups, the Harris's hawk can also take down larger prey, such as jackrabbits.

They nest in small trees, shrubby growth, or cacti. The nests are often compact, made of sticks, plant roots, and stems, and are often lined with leaves, moss, bark and plant roots. They are built mainly by the female. There are usually two to four white to blueish white eggs sometimes with a speckling of pale brown or gray. The nestlings start out light buff, but in five to six days turn a rich brown.

While most raptors are solitary, only coming together for breeding and migration, Harris's hawks will hunt in cooperative groups of two to six. This is an adaptation to the desert climate in which they live. One hunting technique is when a small group flies ahead, scouts, then the other one flies ahead, and scouts, and this continues until prey is bagged and shared. Another is when all the hawks spread around the prey and one individual flushes it.

Harris's Hawks are permanent residents and do not migrate.