Kesko Corporation (Finnish: Kesko Oyj, Swedish: Kesko Abp) is a Finnish retailing conglomerate with its head office in Kalasatama, Helsinki. It is engaged in the grocery trade, building and technical trade, and car trade. It also has operations in Sweden, Norway, Denmark, Estonia, Latvia, Lithuania, and Poland.

Kesko was formed when four regional wholesaling companies that had been founded by retailers were merged in October 1940.

The new Kesko company started operating at the beginning of 1941. The need to purchase goods for the shareholder-retailers and to support their business operations and start cooperation among them resulted in the forming of the K-retailer group.

By the end of the 1940s, Kesko's sales amounted to about 15 billion old Finnish markkas (equivalent to EUR 580 million in 2010), which was about 12% of the overall sales of the central companies operating in the Finnish trading sector.

Kesko's grocery trade division is a key operator in the Finnish grocery trade. The division's main functions include the centralised purchasing of products, selection management, logistics, and the development of chain concepts and the store network.

The division's grocery store chains are K-Market, K-Supermarket and K-Citymarket. In 2021, the chains comprised 1,200 grocery stores, run by some 1,000 independent K-retailers. Over 500 of the stores also offered online grocery sales services. Approximately 50% of Finns live less than a kilometre away from a K-food store.

Formerly Kesko called these four size-grades of their shops K (small), KK (middle-sized), KKK (large), and KKKK (largest), and the chain names were K Extra, K Lähikauppa (= "local shop"), KK Market, KKK Supermarket and KKKK Citymarket; but this naming system has been changed.

Kesko's grocery private brands include Pirkka, Pirkka Parhaat and K-menu.