Henry Wilder Keyes (/ˈkaɪz/;[1] May 23, 1863 – June 19, 1938) was an American Republican politician from Haverhill, New Hampshire.

He was a farmer and cattle breeder, and initiated raising of the Holstein-Friesian breed in the United States.

[3] As a senator, he was noted for not speaking on the floor, even nodding or shaking his head to vote "aye" or "nay."

The one exception was his motion to adjourn during a long winded speech by Senate Finance Committee Chairman Pat Harrison.

Keyes died on June 19, 1938, in North Haverhill, New Hampshire, and is buried at the Oxbow Cemetery in Newbury, Vermont.