Héloïse (French: [elɔ.iz]; c. 1100–01? – 16 May 1163–64?), variously Héloïse d'Argenteuil or Héloïse du Paraclet, was a French nun, philosopher, writer, scholar, and abbess.

Héloïse was a renowned "woman of letters" and philosopher of love and friendship, as well as an eventual high-ranking abbess in the Catholic Church. She achieved approximately the level and political power of a bishop in 1147 when she was granted the rank of prelate nullius.

She is famous in history and popular culture for her love affair and correspondence with the leading medieval logician and theologian Peter Abelard, who became her colleague, collaborator and husband. She is known for exerting critical intellectual influence upon his work and posing many challenging questions to him such as those in the Problemata Heloissae.

Her surviving letters are considered a foundation of French and European literature and primary inspiration for the practice of courtly love. Her erudite and sometimes erotically charged correspondence is the Latin basis for the bildungsroman genre and serve alongside Abelard's Historia Calamitatum as a model of the classical epistolary genre. Her influence extends on later writers such as Chrétien de Troyes, Geoffrey Chaucer, Madame de Lafayette, Thomas Aquinas, Choderlos de Laclos, Voltaire, Rousseau, Simone Weil, and Dominique Aury.

She is an important figure in the establishment of women's representation in scholarship and is known for her controversial portrayals of gender and marriage which influenced the development of modern feminism.