The Nissan Altima is a mid-size car which has been manufactured by Nissan since 1992. It is a continuation of the Nissan Bluebird line, which began in 1957. The Altima is the top selling Nissan model and primarily competes in the mainstream mid-size sedan class in the United States against its main rivals, the Toyota Camry and Honda Accord. It was the second best-selling car in the United States in 2011.

The Altima has historically been larger, more powerful, and more luxurious than the Nissan Sentra but less so than the Nissan Maxima. The first through fourth generation cars were manufactured exclusively in the United States and officially sold in North and South America, along with the Middle East and Australia. For other markets, Nissan sold a related mid-size sedan called theNissan Teana which was between the Altima and Maxima in terms of size. In 2013, the Teana became a rebadged version of the fifth generation Altima.