Ken Jacobsen (born May 2, 1945) is an American former politician who served as a Democratic member of the Washington State Senate.

He served as the Democratic Caucus Vice Chairman in 2003, the Majority Caucus Vice Chairman in 1999 and 2001, and he is a former chair of the House Higher Education Committee.

In the State Senate, Jacobsen represented the Seattle neighborhoods of Wedgwood, View Ridge, Sand Point, Roosevelt, Northgate, Maple Leaf, and Lake City.

Born in Dannebrog, Nebraska, of "Postcard from Nebraska" fame and raised in northeast Seattle, Senator Jacobsen enjoys bird watching, hummingbird and butterfly gardening.

Board member of Scholarship America and Washington Dollars for Scholars; U.S. Foundation of the Universidad Del Valle de Guatemala; Friends of the University of Washington Library; Seattle Audubon Society; American Indian Endowment Committee; Ravenna & Thornton Creek Alliances'; Bring the Purple Martin Back to Seattle Committee; Education Advisory Committee Nordic Heritage Museum; Founder of the Annual Raoul Wallenberg Dinner.