William Magan Campion (1820–1896) was a lecturer in Mathematics and the President of Queens' College, Cambridge, from 1892 until his death.

He was admitted as pensioner to Queens' College, Cambridge, in 1845 to read mathematics; he was 4th Wrangler.

He was rector of the St Botolph's Church, Cambridge, 1862-1892, and a rural dean, 1870-1892, and honorary canon of Ely Cathedral, 1879-1896.

In conjunction with W. J. Beaumont, he wrote a learned yet popular exposition of the Book of Common Prayer, entitled The Prayer-Book Interleaved.

He died in the President's Lodge at Queens' College on 20 October 1896 and is buried in the Mill Road Cemetery, Cambridge.