The Calusa are a Native American people of Florida's southwest coast.

Calusa society develops from that of archaic peoples of the Everglades region; at the time of European contact, the Calusa are the people of the Caloosahatchee culture.

They are notable for having developed a complex culture based on estuarine fisheries rather than agriculture.

Calusa territory reaches from Charlotte Harbor to Cape Sable, all of present-day Charlotte and Lee counties, and may have included the Florida Keys at times.

They have the highest population density of south Florida; estimates of total population at the time of European contact range from ten thousand to several times that, but these are still speculative.Calusa political influence and control also extend oer other tribes in southern Florida, including the Mayaimi around Lake Okeechobee and the Tequesta and Jaega on the southeast coast of the peninsula.

Calusa influence may have also extended to the Ais tribe on the central east coast of Florida.