Rosalind Elsie Franklin (July 25, 1920 - April 16, 1958) was a molecular biologist who assisted in the discovery of the structure of DNA.

Franklin was born and died in London, England.

Rosalind Franklin earned her doctorate degree in physical chemistry at Cambridge University in 1945. She learned X-ray diffraction techniques during three years' study in Paris at the Laboratoire Central des Services Chimiques de L'Etat, returning to England to work as a research associate at King's College London with John Randall.

Without her knowledge, another Randall research associate, Maurice Wilkins showed some of her X-ray diffraction photographs of DNA to James Watson, whereupon Watson, with Francis Crick, succeeded in determining the molecule's structure, and published in Nature magazine on April 25, 1953 an article describing the double-helical structure of DNA. Articles by Wilkins and Franklin illuminating their X-ray diffraction data supporting the findings of Watson and Crick were published in the same edition.

Franklin died of ovarian cancer in 1958; it was almost certainly caused by exposure to radiation in the course of her research. Wilkins, Watson, and Crick were awarded the Nobel Prize in Physiology or Medicine in 1962.

Much has been written on the role that Franklin played in the discovery of the structure of DNA. While it is clear that her work was an important basis for determining DNA's structure, the correct deduction itself was mostly the work of Watson and Crick. Whether, given time, Franklin would have reached the same deduction in the rather competitive race (including such figures as Linus Pauling) to discover the structure of DNA is unknown.