Isabella of Portugal (or Isabel in Portuguese) (February 21 1397 - December 17 1471) was the only surviving daughter of king John I of Portugal and his wife Philippa of Lancaster. She was the sister, amongst others, of Henry the Navigator, Pedro, duke of Coimbra and king Edward of Portugal. Isabella was born in Évora and spent her youth in the Portuguese court in Lisbon.

In 1430 she married Philip III, duke of Burgundy. They had three sons: Anthony and Joseph (who died in childood) and Charles the Bold (born November 10 1433). Isabella was a very refined and intelligent woman, who liked to be surrounded by artists and poets. She funded numerous scholarships and was a patron of the arts. Also in politics, she had a great influence on her son, but especially on her husband, whom she represented on several diplomatic conferences. She died in Dijon in 1471.