Ebenezer Oliver Grosvenor, Jr. (January 26, 1820 – March 10, 1910) was an American politician from the U. S. state of Michigan.

Grosvenor was born in Stillwater, New York and received a common school and academic education.

Also in that year, he was commissioned a colonel on Governor Austin Blair's staff and was also president of the state military board.

Grosvenor served a member and president of the board of state building commissioners from 1871 to 1879.

In 1903, at the age of 83, he became a member of the Michigan Republican Party State Central Committee.