Battistina Vernazza (secular name Tommasina Vernazza) (born at Genoa, 1497; died there, 1587) was an Italian canoness regular and mystical writer.
Her father, Ettore Vernazza, was a patrician, founder of several hospitals for the sick poor in Genoa, Rome, and Naples. Her godmother was Catherine Fieschi-Adorno.
At the early age of 13, Tommasina entered the monastery of Santa Maria delle Grazie, and became a canoness regular, taking the name of Battistina. She filled at various times the office of treasurer, novice-mistress, and prioress.
She wrote, among other things, a commentary on the Pater Noster; "The Union of the soul with God"; "Of the knowledge of God"; "Of prayer"; "Of the heavenly joys and of the means of attaining them"; "Of those who have risen with Christ"; meditations, spiritual canticles, and letters to eminent men of her time. Possevin speaks of her writings as inspired. Her works were published at Venice in 3 vols. in 1588. They have been published many times since.