John Rädecker (Amsterdam 1885-1956 Amsterdam) was a painter and, more prominently, a sculptor, best known for his work on the National Monument on Dam Square in Amsterdam. He is associated with the Amsterdam School but his style also shows affinities with the Bergen School.

He was the son of the German-born sculptor Wilhelm Rädecker and Anna Gosseling. John studied at the Academy of Fine Arts in Rotterdam and attended evening classes at the Rijksacademie in Amsterdam, where he was taught by B.J.W.M. van Hove.

His breakthrough occurred around 1910. During this period, he created luminist paintings. In Paris, from 1911 to 1914, he worked in an abstract style. After World War I, he gained international recognition as an influential expressionist sculptor with a highly personal blend of style influences. Rädecker enriched sculpture by creating visionary heads and human and animal figures in a style previously unknown to the art form. His work emphasizes the sensitivity and sensuality of form. His sculptures are often coarse in shape, leaving a mysterious impression. He also created many masks with a mystical, often dreamy expression. Like other artists of his time, Rädecker was fascinated by ethnographic art from Africa and Oceania, mysticism, and theosophy. The symbolism from the dream world manifested in Rädecker's work through enlarged forms and expressions of moods. Some of his sculptures were incorporated into the architecture of the Amsterdam School.
From 1916, John Rädecker was a member of De Nieuwe Kring, a group of visual artists and literary figures inspired by a sense of community, establishing themselves in an artists' colony around Bergen.

In July 1926, the artist association De Brug was founded, modeled after the earlier German association Die Brücke. Its goal was to introduce New Objectivity (Nieuwe Zakelijkheid) in Dutch painting. Founding members included well-known artists such as Dick Ket, Johan Polet, Charley Toorop, and John Rädecker. Rädecker maintained close friendships, including with Charley Toorop, and collaborated with poets and writers, such as Holst, for the monument on Dam Square.

He taught his son Jan Willem Rädecker and other artists like G. Leijden van Amstel, Hildo Krop, Oswald Wenckebach, H.J.B. Schippers, and G. van der Wagt. His brothers Toon and Willem were also sculptors. In the 1920s and 1930s, John Rädecker was regarded as the most important Dutch sculptor. He collaborated with his sons on the National Army Monument on the Grebbeberg, known as the Lion Monument. His sons also completed the National Monument, a project he worked on with his brother Anton. On the day the first statues of love and freedom were placed, John Rädecker passed away. Helene Kröller-Müller, a well-known collector, owned many of his works, and as a result, a significant portion of Rädecker's art can be found in the Veluwe.