Leonora Marescoe, née Lethieullier or Lethiulliers (1637 – 1715) was an English merchant.
Leonora Marescoe was the daughter of a successful merchant and was one of the most noted members of the merchant class in Restoration period London, part of a London colony of Huguenots from the Spanish Netherlands.
She married in 1658 to Charles Marescoe, with the same background and who was one of the most successful merchants in London during the 1660s.
The Marescoe-Joyes belonged to the greatest elite trading houses in London.
One of its main trades was that of copper with contacts in the Baltic Sea and Stockholm, where one of her most noted business partners was Debora van der Plas.