John Wishart FRSE (28 November 1898 – 14 July 1956) was a Scottish mathematician and agricultural statistician.
He worked successively at University College London with Karl Pearson, at Rothamsted Experimental Station with Ronald Fisher, and then as a reader in statistics in the University of Cambridge where he became the first Director of the Statistical Laboratory in 1953. He was elected a Fellow of the Royal Society of Edinburgh in 1931, and edited Biometrika from 1937. The Wishart distribution is named after him.
Wishart died at age 57 in a bathing accident in Acapulco while representing the Food and Agriculture Organization on a mission to set up a research centre.