Buick is a brand of automobile built in the United States, Canada, and China by General Motors Corporation. Buicks are sold in North America, China, the CIS countries, and the Middle East.

Buick originated as an independent motor car manufacturer, the Buick Motor Company, incorporated on May 19, 1903 by David Dunbar Buick (who invented the overhead valve engine on which the company's success was based) in Flint, Michigan. In 1904 the struggling company was taken over by James Whiting, who brought in William C. Durant to manage his new acquisition. Buick soon became the largest car maker in America. Using the profits from this, Durant embarked on a series of several dozen corporate acquisitions, calling his new mega-corporation General Motors.

Unlike some of GM's other brands, Buicks are not marketed globally, although in the early years of the marque Buick had a substantial export presence. In pre-World War II China, for example, one in five cars were Buicks. Currently most Buick sales are restricted to the United States and Canada. However, Buick has attracted a considerable market in a few countries. Since 1999, a Chinese version of the Buick Century/Regal has been produced and sold in China under Shanghai GM and has proven to be popular among upscale, professional families, establishing Buick as GM's most popular brand in China. In addition, Buick of China also sells the subcompact Sail, sourced from GM's Asian operations and based on the Opel Corsa B, the compact Excelle, based on the Daewoo Lacetti/Nubira, and a modified version of the Venture/Montana/Silhouette/Sintra minivan named the GL8. In June, 2005, Buick announced that it will buld a car named the Buick Royaum in Australia for export to China, based on the Holden Statesman and Caprice luxury cars. Buick has stated that it expects China to become its second largest market.