William Smyth (February 2, 1797 – April 3, 1868) was an American academic and writer on mathematics and other subjects.

William Smyth was born in Pittston, Massachusetts (which became part of Maine is 1820) on February 2, 1797.

The Bowdoin College Department of Mathematics Smyth Prize is named in his honor.

Smyth was an ardent abolitionist of slavery and supporter of the temperance movement.

While at Bowdoin, Smyth supported the effort to the First Parish Church, which is now on the National Register of Historic Places.