William Gaston Steele (December 17, 1820, Somerville, New Jersey – April 22, 1892, Somerville, New Jersey) was a 19th Century American banker who served as a Democratic Party politician.

He served two terms as a U.S. congressman, representing New Jersey's 3rd congressional district from 1861 to 1865.

Steele was born in Somerville, New Jersey on December 17, 1820, where he attended the public schools and Somerville Academy.

His vote on the Thirteenth Amendment is recorded as nay.

After leaving Congress, he engaged in the brokerage business.