James Mabbe or Mab (1572–1642) was an English scholar and poet, and a Fellow of Magdalen College, Oxford. He was involved in translations from Spanish, in particular of some of the work of Cervantes. He made a translation, in 1622, of the Picaresque novel by Mateo Alemán, Guzmán de Alfarache, and also, in 1631, Celestina, or the Tragicomedy of Calisto and Melibea, a 300-page play, or "novel in dialogue," by Fernando de Rojas.
James Mabbe may also be the "I. M." who wrote the fourth commendatory verse to the First Folio of Shakespeare's plays (1623), given that his friend and colleague Leonard Digges wrote the third.