Fåhraeus, Fåhræus, or Fahraeus is a Swedish surname. It can refer to:
(b. 1965), Swedish inventor (1828-1867), Swedish statistician (1817-1900), Swedish politician (1862-1936), Swedish priest (b. 1973), Swedish game designer (1796-1865), Swedish politician (1863-1944), Swedish writer and parent of Robin Fåhræus (1762-1789), musician (1803-1875), Swedish philanthropist Olof Fåhræus (1796–1884), Swedish politician and entomologist (b. 1968), Swedish sculptor Robin Fåhræus (1888-1968), Swedish pathologist and hematologist (1905-1989), Swedish gynecologist (1865-1950), Swedish historian
See also Fåhræus effect, named for Robin Fåhræus Fåhræus–Lindqvist effect, also named for Robin Fåhræus Fahraeusia and Fahraeusiella, genera of beetles named for Olof Immanuel von Fåhraeus