D
- Valerie Daggett, American bioengineer
- Anders Dahl (1751–1789), namesake of the Dahlia
- W.H. Dall (1845–1927), American naturalist and malacologist.
- Charles Darwin (1809–1882), British naturalist
- Erasmus Darwin (1731–1802), doctor, naturalist, grandfather of Charles
- Charles Davenport (1866–1944), American biologist and eugenicist, founded the Eugenics Record Office at Cold Spring Harbor Laboratory
- Armand David (1826–1900), French zoologist and botanist
- Bernard Davis (1916–1994), American biologist
- Richard Dawkins (born 1941), British evolutionary biologist
- Pierre Antoine Delalande (1787–1823), French naturalist
- Max Delbrück (1906–1981), German physicist and biologist known for work on the replication mechanism of viruses
- Richard Dell (1920–2002), New Zealand malacologist
- Stefano Delle Chiaje (1794–1860), Italian
- Paul Émile de Puydt (1810–1888), Belgian botanist
- René Louiche Desfontaines (1750–1833), French botanist
- Gérard Paul Deshayes (1795–1875), French geologist and conchologist.
- Anselme Gaëtan Desmarest (1784–1838), French zoologist
- Ernst Dieffenbach (1811–1855), German naturalist
- Johann Jacob Dillenius (1684–1747), German botanist
- Lewis Weston Dillwyn (1778–1855), British botanist and conchologist
- Walter Dobrogosz (born 1933), American microbiologist, discoverer of Lactobacillus reuteri
- Theodosius Dobzhansky (1900–1975), American geneticist and evolutionary biologist
- Rembert Dodoens (1517–1585), Flemish botanist
- Anton Dohrn (1840–1909), German marine biologist
- David Don (1799–1841), British botanist
- James Donn (1758–1813), English botanist
- Jean Dorst (1924–2001), French ornithologist
- Henry Doubleday (1808–1875), British entomologist
- David Douglas (1799–1834), Scottish botanist
- Jonas C. Dryander (1748–1810), Swedish botanist
- Félix Dujardin (1802–1860), biologist
- Renato Dulbecco (1914–2012), biologist
- Ronald Duman, Biological psychiatry
- André Marie Constant Duméril (1774–1860), French zoologist
- Michel Felix Dunal (1789–1856), French botanist
- Robin Dunbar (born 1947), Italian virologist
- Gerald Durrell (1925–1995), British naturalist
Read more about this topic: List Of Biologists