Robert de Beaumont, 1st Earl of Leicester and Count of Meulan (died June 5, 1118) was a powerful English and French nobleman, revered as one of the wisest men of his age. Chroniclers speak highly of his eloquence, his learning, and three kings of England valued his counsel.

He was the eldest son of Roger de Beaumont and Adeline of Meulan , and an older brother of Henry de Beaumont, 1st Earl of Warwick. He accompanied William the Conqueror to England in 1066, where his service earned him more than 91 lordships and manors. When his mother died in 1081, Robert inherited the title of Count of Meulan . In 1100 Robert was with William Rufus in the New Forest when the latter died under sudden and violent circumstances. He then pledged alligience to William Rufus' brother, Henry I of England, who created him Earl of Leicester in 1107.

In 1096 he married Isabella de Vermandois, daughter of Hugh Magnus and a scion of the French royal family. Their children were:

1. Waleran IV de Beaumont, Count of Meulan (born 1104)
2. Robert de Beaumont, 2nd Earl of Leicester (born 1104)
3. Hugh de Beaumont, Earl of Bedford (born c. 1106)
4. Isabel de Beaumont, a mistress of King Henry I of England and the mother of Strongbow.

According to Henry of Huntingdon, Robert died of shame after "a certain earl carried off the lady he had espoused, either by some intrigue or by force and stratagem." His wife Isabella remarried in 1118 to William de Warenne, 2nd Earl of Surrey.