Karl Hilding Hagberg (28 October 1899 – 17 December 1993) was a Swedish communist politician.

As a miner working in Malmberget he joined the Communist Party of Sweden in his youth.

As leader of the Communist Party of Sweden, Hagberg upheld a clearly pro-Soviet line.

He supported the Soviet crushing of the Hungarian Revolution of 1956 and he also defended the building of the Berlin Wall as "serving the cause of peace".

His memoirs, titled Jag är och förblir kommunist ("I am and will remain a communist"), were published in 1995.