Keefer may refer to:
- Charles Keefer (1852–1932) was one of Canada's pioneering engineers
- Chester Keefer (1897–1972), American physician, medical researcher, and medical school dean
- Don Keefer (1916–2014), American actor originally from Pennsylvania
- Francis Henry Keefer (1860–1928), Canadian lawyer and politician
- Janice Kulyk Keefer (born 1952), Canadian novelist and poet
- John Keefer Mahony (1911–1990), Canadian recipient of the Victoria Cross
- Keefer-Brubaker Farm (Oscar Fogle Farm), a historic home and farm complex located at Taneytown, Carroll County, Maryland, United States
- Mel Keefer (1926–2022), American artist
- Philip B. Keefer (1875–1949), United States Navy sailor and a recipient the Medal of Honor for his actions during the Spanish–American War
- Thomas Keefer (1821–1915), Canadian civil engineer
- Keefers, British Columbia, a railway point and ghost town in British Columbia, Canada