The year 1709 in science and technology included many events, some of which are listed here.

See also: 1708 in science, other events of 1709, 1710 in science and the list of years in science.

Births

• February 24 - Jacques de Vaucanson, French engineer and inventor (died 1782)
• March 3 - Andreas Sigismund Marggraf, German chemist (died 1782)
• March 10 - Georg Steller, German naturalist (died 1746)
• August 8 - Johann Georg Gmelin, German botanist (died 1755)

Deaths

• June 30 - Edward Llwyd, Welsh naturalist (born 1660)