Ian Graeme Barbour (born 5 October 1923), is an American scholar on the relationship between science and religion. According to the Public Broadcasting Service his mid-1960s Issues in Science and Religion "has been credited with literally creating the contemporary field of science and religion."

In the citation nominating Barbour for the 1999 Templeton Prize, John B. Cobb wrote "No contemporary has made a more original, deep and lasting contribution toward the needed integration of scientific and religious knowledge and values than Ian Barbour. With respect to the breadth of topics and fields brought into this integration, Barbour has no equal"

He received his BS in Physics from Swarthmore College, his MS in Physics from Duke University in 1946, and a PhD in Physics from the University of Chicago in 1950.

He earned a BDiv in 1956 from Yale University's Divinity School. Barbour taught for many years at Carleton College with appointments as professor of religion and as Winifred and Atherton Bean Professor Emeritus of Science, Technology and Society. He has held emeritus honors there since 1986.

Barbour gave the Gifford lectures from 1989 – 1991 at the University of Aberdeen. These lectures led to the book Religion in an Age of Science. He was awarded the Templeton Prize in 1999 for Progress in Religion in recognition of his efforts to create a dialogue between the worlds of science and religion.