Gilbert de Clare, 7th Earl of Hertford and 8th Earl of Gloucester (1291 – 24 June 1314) was a powerful English noble and the grandson of Edward I.

His mother was Joan of Acre, who was the daughter of Edward I and his first wife, Eleanor of Castile. His father was the 6th Earl of Hertford. He succeeded to the titles in 1295, at the age of 4. But he held them for only two years. His stepfather, Ralph de Monthermer, 1st Baron Monthermer, was allowed, by the grace of Edward I of England, to hold the titles of Earl of Hertford, Earl of Gloucester from 1297 to 1307. The titles were then transferred back to Gilbert, who was now 15, and he held them until his death.

Gilbert was raised with Edward II and proved to be a moderating influence amongst the king and nobility before his death. It was due to his close relation with the king that Gilbert was allowed to succeed to his titles before attaining his majority (which would have been when he was 18).

He died young, being killed in the Battle of Bannockburn. He died without issue, although there was a 2-year dispute with his widow, Maud, who claimed to be pregnant throughout this time. In spite of having the king's backing, after more than a year and a half of litigation, it was acknowledged that there was no possible way that Maud could still be pregnant by Gilbert and his lands were divided amongst three of his sisters, Elizabeth, Eleanor and Margaret.

By the provisions of the marriage contract of his parents, their joint possessions could only be inherited by a direct descendant. Although he had also two older half-sisters, his three full sisters therefore inherited his property.