Eston Hemings Jefferson (May 21, 1808 – January 3, 1856) was born into slavery at Monticello, the youngest son of Sally Hemings, a mixed-race enslaved woman. Most historians who have considered the question believe that his father was Thomas Jefferson, the third president of the United States. Evidence from a 1998 DNA test showed that a descendant of Eston matched the Jefferson male line, and historical evidence also supports the conclusion that Thomas Jefferson was probably Eston's father. Many historians believe that Jefferson and Sally Hemings had six children together, four of whom survived to adulthood. Other historians disagree.

Jefferson freed Eston and his older brother Madison Hemings in his will, as they had not yet come of age at his death. They each married and lived with their families and mother Sally in Charlottesville, Virginia, until her death in 1835. Both brothers and their young families moved to Chillicothe, Ohio, to live in a free state, where Eston Hemings earned a living as a musician and entertainer.

In 1852 Eston moved with his wife and three children to Madison, Wisconsin, where they changed their surname to Jefferson and entered the white community. Their sons both served in the Union Army, and the older one, John Wayles Jefferson (see also, John Wayles), achieved the rank of colonel. After the war, he moved to Memphis, Tennessee, becoming a wealthy cotton broker and never married.

Eston's other children, Beverly (Beverly was also the name of Eston's oldest brother) and Anna Jefferson, married into the white community, and their descendants have identified as white. Beverly Jefferson's five sons were educated and three entered the professional class as a physician, attorney, and manager at the railroad. One of their male-line descendants was tested in the 1998 DNA study that found the link to the Jefferson-male line.

What is known of Eston's life is derived from his brother Madison's 1873 memoir, a few entries in Thomas Jefferson's Farm Book, a handful of contemporary newspaper accounts, various census and land/tax records, and the family history of his descendants.

Eston was born into slavery as the youngest son of the enslaved Sally Hemings. As she was one of the six mixed-race children of Betty Hemings and John Wayles (Jefferson's father-in-law), she and her siblings were half-siblings to Jefferson's wife Martha Wayles and were three-quarters European in ancestry, as their mother had a white father. The historians Philip D. Morgan and Joshua D. Rothman have written about the numerous interracial relationships in the Wayles-Hemings-Jefferson families and the region, often with multiple generations repeating the pattern. The large Hemings family, with Betty Hemings as matriarch, was at the top of the slave hierarchy at Monticello; its members working as domestic servants, chefs, craftsmen and artisans.

Sally Hemings had light duties, and as children, Eston and his siblings "were permitted to stay about the 'great house', and only required to do such light work as going on errands." Like their older brother Beverley, at age 14 Madison and Eston each began training in carpentry, under tutelage of their uncle John Hemmings, the master woodworker at Monticello. All three brothers learned to play the violin (Jefferson also is known to have regularly played when he was younger, and his younger brother Randolph, according to the ex-slave Isaac Granger, "used to come out among black people, play the fiddle & dance half the night".)

Madison and Eston were freed in 1827, in accordance with President Jefferson's will. (Madison was 22; Eston was freed at 19.) Additionally, Jefferson's will petitioned the legislature to allow the Hemingses to stay in Virginia after being freed, unlike most freed slaves. In his 1873 memoir, Madison said the Hemings children were freed as a result of a promise Jefferson made to Sally Hemings.