Achille Vertunni (Naples, March 1826 –1897) was an Italian painter.
Vertunni was a Neapolitan nobleman who initially studied law under Roberto Savarese, although his family had intended for him to become an architect, and enrolled him to study mathematics under Ferdinando de Luca. Vertunni however gravitated towards the visual arts, causing a rift with his father, who would not countenance his son working as a penniless artist and eventually disinherited Achille. He enrolled to study landscape painting under Salvatore Fergola, and after just eight months went on to serve his first apprenticeship under the historical painter Giuseppe Bonolis, and eventually with Francesco De Sanctis. He is said to have been influenced by Gabriele Smargiassi.
In 1851 Vertunni entered the yearly competition held by the Accademia di Belle Arti di Napoli (Naples Academy of Fine Arts), but the judges failed to agree on a single winner for the first prize, opting instead for awarding a silver medal each, ex equo, to Vertunni and Filippo Palizzi, a fellow pupil of Bonolis', rumoured to have been the judges' favourite, owing to his links with the Academy.
As part of their prize, the two artists received a stipend to study in Rome and in 1853 Vertunni moved there, painting the Santa Margherita da Cortona for the Esposizione di Firenze of 1861. In the same year, he painted La Pia de' Tolomei and Dante in the Forest. He faced difficulty in selling the latter, as an innovative painting portraying Pia not in a classic portrait, but against a Maremman landscape; in spite of some financial difficulties, Vertunni persevered and became a prolific painter.
Later in life, he was named Cavaliere dell'Ordine della Corona d'Italia (Order of the Crown of Italy), and honorary professor of the Reale Istituto di Belle Arti di Napoli and of the Brera Academy of Milan.