The Louisa Gross Horwitz Prize for Biology or Biochemistry is an annual prize awarded by Columbia University to a researcher or group of researchers who have made an outstanding contribution in basic research in the fields of biology or biochemistry.
The prize was established at the bequest of S. Gross Horwitz and is named to honor his mother, Louisa Gross Horwitz, the daughter of trauma surgeon Samuel D. Gross. The prize was first awarded in 1967.
As of October 2018, 51 (50%) of the 101 prize recipients have subsequently been awarded the Nobel Prize in Physiology or Medicine (40) or Chemistry (11). It is regarded as one of the important precursors of a future Nobel Prize award.