John Philippe Rushton (December 3, 1943 – October 2, 2012) was a Canadian psychologist and author. He taught at the University of Western Ontario until the early 1990s, and became known to the general public during the 1980s and 1990s for promoting anti-Black racism through his widely discredited research on race and intelligence, race and crime, and other purported racial correlations.

Rushton's work has been heavily criticized by the scientific community for the poor quality of its research, with many academics arguing that it was conducted under a racist agenda. From 2002 until his death, he served as the head of the Pioneer Fund, an organization founded in 1937 to promote eugenics, which has been described as racist and white supremacist in nature, and as a hate group by the Southern Poverty Law Center. He also published articles in and spoke at conferences organized by the white supremacist magazine American Renaissance.

Rushton was a Fellow of the Canadian Psychological Association and a onetime Fellow of the John Simon Guggenheim Memorial Foundation. In 2020, the Department of Psychology of the University of Western Ontario released a statement stating that "much of [Rushton's] research was racist", was "deeply flawed from a scientific standpoint", and "Rushton's legacy shows that the impact of flawed science lingers on, even after qualified scholars have condemned its scientific integrity." As of 2021, Rushton has had six research publications retracted for being scientifically flawed, unethical, and not replicable, and for advancing a racist agenda despite evidence contradictory to his claims.

Rushton was born in Bournemouth, England. During his childhood, he emigrated with his family to South Africa, where he lived from age four to eight (1948–1952). His father was a building contractor and his mother came from France. The family moved to Canada, where Rushton spent most of his teen years. He returned to England for university, receiving a B.Sc. in psychology from Birkbeck College at the University of London in 1970, and, in 1973, his Ph.D. in social psychology from the London School of Economics for work on altruism in children. He continued his work at the University of Oxford until 1974.

Rushton taught at York University in Canada from 1974 to 1976 and the University of Toronto until 1977. He moved to the University of Western Ontario and was made full professor (with tenure) in 1985. He received a D.Sc. from the University of London in 1992. His controversial research has sparked political debates, and Ontario Premier David Peterson called Rushton a racist. In 2005, The Ottawa Citizen described Rushton as the most famous university professor in Canada.

He published more than 250 articles and six books, including two on altruism, and one on scientific excellence, and co-authored an introductory psychology textbook. He was a signatory of the opinion piece "Mainstream Science on Intelligence."

Rushton died of cancer on October 2, 2012, at the age of 68.

Early in his career, Rushton did research on altruism. He theorized a heritable component in altruism and developed Genetic Similarity Theory, which is an extension of W.D. Hamilton's theory of kin selection. It holds that individuals tend to be more altruistic to individuals who are genetically similar to themselves even if they are not kin, and less altruistic, and sometimes outwardly hostile, to individuals who are less genetically similar. Rushton describes "ethnic conflict and rivalry" as "one of the great themes of historical and contemporary society", and suggests that this may have its roots in the evolutionary impact on individuals from groups "giving preferential treatment to genetically similar others". According to Rushton: "the makeup of a gene pool [i.e., a human population's total reservoir of alternative genes] causally affects the probability of any particular ideology being adopted".