Lemaître, Lemaitre, Le Maitre, or variation, is a French surname meaning "the master" – derived from the Latin word "magister".

Notable people with the surname include:

• Anne Lemaître (born 1957) Belgian applied mathematician
• Delphine Philippe-Lemaître, (1798–1863), French historian, archaeologist, botanist
• Frédérick Lemaître (1800–1876), French actor and playwright
• Georges Lemaître (1894–1966), Belgian Roman Catholic priest and astronomer, who formulated the "Big Bang" theory of cosmologic origin of the physical universe.
  • Named for Georges Lemaître:
    • Lemaître (crater), an impact crater on the Moon
    • 1565 Lemaître, a minor planet
    • the Friedmann–Lemaître–Robertson–Walker metric
    • the Lemaître metric
    • the Lemaître–Tolman metric
    • Lemaitre (band), Norwegian indie electronic band
    • Georges Lemaître ATV, an uncrewed spacecraft
• Jules Lemaître (1853–1914), French critic and dramatist
• Maurice Lemaître (1928–2018), French painter
• Jean Lemaître (mechanical engineer) (1898–1974), Belgian mechanical engineer, who developed a steam locomotive exhaust

• Christophe Lemaitre (born 1990), French sprinter
• Pierre Lemaitre (born 1951), a French author and a screenwriter
• Rafael Lemaitre, French carcinologist

• George D. LeMaitre (1933–2018), American vascular surgeon
  • LeMaitre Vascular, company founded by the surgeon in 1986
• Jade Le Maître (fl. 2010s), a roboticist

• Lemaitre (band), Norwegian indie electronic duo

• All pages with titles containing Le-Maitre or Le-Maitres
• All pages with titles containing Lemaitre or Lemaitres
• Le Maistre (surname)
• Maitre (surname)