The Yaocomico /jaʊˈkɒməkoʊ/, also spelled Yaocomaco, were an Algonquian-speaking Native American group who lived along the north bank of the Potomac River near its confluence with the Chesapeake Bay in the 17th century.

The settlers who arrived to found the English colony of Maryland purchased land for their first settlement from the Yaocomico.

Historians believe this was mostly due to epidemics of newly introduced infectious disease and to pressure from European settlers and other Native groups.

As a result of the meeting, the Yaocomico traded approximately 30 acres (12 ha) of land for a variety of European-made metal tools and cloth.

[3] Father Andrew White, a Jesuit missionary priest and early Maryland settler, described the Yaocomico in detail.

[4] European accounts claimed the Yaocomico were ready to sell the land to the Maryland colonists because they were being threatened by Iroquoian-speaking tribes from the north, specifically the Susquehannock and Seneca, the latter part of the Iroquois Confederacy.

[1] Despite relations with the Piscataway and the larger Powhatan Confederacy to the south, the Yaocomico had apparently decided to abandon the area before the arrival of Europeans.

[4] Both the Yaocomico and their neighbors had been raided repeatedly by groups of Susquehannock warriors based further up the Chesapeake, along what the settlers named the Susquehanna River.

Such raids had pushed most Algonquian Natives out of the lands along the upper Chesapeake Bay, concentrating them in the south, where they encountered English settlers.