`"Who's Afraid of Red, Yellow and Blue" is primarily the title of a famous series of four large-scale paintings by American artist Barnett Newman, created between 1966 and 1970. Newman intended the title as a challenge to the rigid, "didactic" rules of De Stijl, a movement led by Piet Mondrian that restricted art to primary colors and geometric forms. Newman wanted to "liberate" these colors, using them for pure emotional expression rather than mathematical balance. The title is a play on the 1962 Edward Albee play Who's Afraid of Virginia Woolf?, which itself riffs on the song "Who's Afraid of the Big Bad Wolf?". In the play, the phrase signifies a fear of living without illusions. Newman applied this to art, suggesting people were "afraid" of pure, unadorned color and abstraction without traditional representation.

The title proved prophetic, as the paintings actually provoked intense fear and anger in some viewers. Two works in the series were famously attacked. In 1986, Gerard Jan van Bladeren slashed Who's Afraid of Red, Yellow and Blue III at the Stedelijk Museum with a box cutter because he felt abstract art was a "plague".

A controversial restoration later "ruined" the work by painting over it with a roller, leading some to say it had been "murdered" twice. `