William Woodbridge McNair (January 4, 1836 – September 15, 1885) was a lawyer and Democratic politician who served as mayor of St. Anthony, Minnesota.

He attended schools in Genesee, New York and at Canandaigua Academy before moving to Racine, Wisconsin in 1855 to study law under James Rood Doolittle.

After two years he moved to Minneapolis where he continued his studies and gained admission to the bar in 1857.

He also held a number of political offices including two terms as mayor of St. Anthony (shortly prior to its absorption into Minneapolis) from 1869 to 1871.

In 1876 he was the Democratic nominee for United States Representative but lost to Jacob H. Stewart.