William B. Woodin (September 25, 1824 – November 1, 1893) was an American lawyer and politician from New York.

Then he studied law, was admitted to the bar, and commenced practice in Aurora.

In 1877, he was accused of having taken bribes from William M. Tweed, but a State Senate investigation concluded that he was innocent.

He was a delegate to the 1880 Republican National Convention where he opposed Roscoe Conkling's plan to nominate Ulysses S. Grant for a third term.

In 1882, Woodin abandoned the Republican candidate for Governor, Charles J. Folger, and supported Democrat Grover Cleveland instead.