Hyacintha Mariscotti, T.O.R., or Hyacintha of Mariscotti, was an Italian religious sister of the Third Order Regular of St. Francis. She was born in 1585 of a noble family at Vignanello, in the Province of Viterbo, and died 30 January 1640 in Viterbo, noted for the depth of her spiritual gifts. She is honored as a saint in the Catholic Church.