James Jeffrey Binney, FRS, FInstP (born 12 April 1950) is a British astrophysicist. He is a professor of physics at the University of Oxford. Binney is known principally for his work in theoretical galactic and extragalactic astrophysics, though he has made a number of contributions to areas outside of astrophysics as well.

Binney has received a number of awards and honours for his work, including the Maxwell Prize of the Institute of Physics in 1986, the Brouwer Award of the American Astronomical Society in 2003, the Dirac Medal of the Institute of Physics in 2010, the Eddington Medal in 2013, and the Isaac Newton Medal in 2023. He has been a fellow of the Royal Astronomical Society since 1973, and was made a Fellow of the Royal Society and a fellow of the Institute of Physics, both in 2000. He sits on the European Advisory Board of Princeton University Press.