Donald R. Knabe (born October 15, 1943, in Illinois) is a member of the Los Angeles County Board of Supervisors, serving the Fourth District. Knabe is the current Chairman for the 2010 session. He recently was reelected on the June 3, 2008 election.

Knabe attended Graceland University and graduated with a degree in business administration. After enlisting in the U.S. Navy, Knabe and his new wife, the former Julie Gillbreath, settled in Cerritos. The Knabes owned a small business, and Knabe entered politics in 1978 as one of several candidates for the GOP nomination to replace Del Clawson as Congressman from the 33rd District (Downey-Norwalk-Whittier). Knabe lost to La Marida Mayor Wayne Grisham, but carried his home area, and in 1980 was elected to the Cerritos City Council on the basis of growth issues. Knabe took a job with Supervisor Deane Dana's office in 1982, soon advancing to Chief of Staff.

In 1987, Knabe considered running as a Republican for the state Senate in a special election. However, he backed down in favor of Wayne Grisham (whose Congressional seat had been redistricted and was now a state Assemblyman). Grisham lost the special election to Democratic Norwalk City Councilman Cecil Green by a larger-than expected margin, and Republicans immediately concluded that the younger, more energetic Knabe should have been the nominee. Knabe retired from the City Council in 1988 to run for the state Senate. After a hard-fought and expensive campaign, Green defeated Knabe by 51% to 49%.