Antoine-George-Prosper Marilhat, usually known as Prosper Marilhat, was a French Orientalist painter. Many of his most successful works were based on the sketches he drew during the time he spent in Egypt in 1831–1832.

He was born in Vertaizon. Encouraged by local artists, Marihat began painting at an early age. Although his parents wanted him to work in the cutlery business of Thiers, Puy-de-Dôme where he lived, the Baron de Barante convinced them he was more suited to an artistic career. He went to Paris in 1829 where he studied under Camille Roqueplan, exhibiting for the first time at the Paris Salon in 1831 with his Site d'Auvergne.

In May 1831, Marilhat was invited by Charles von Hügel to join him on a lengthy expedition but he only accompanied him as far as Alexandria. Over the following months, from October 1831 to May 1833, he completed ten albums of sketches there which would form the basis of his later paintings. In 1835, he travelled through Italy and spent 1836 in Provence. He exhibited in all the Paris Salons from 1837 to 1841 as well as at the Salon of 1844. While he specialized in architectural paintings and landscapes, he also painted portraits including one of his friend Théodore Chassériau which is now in the Louvre.

From 1840 to 1844, Marilhat painted a number of works inspired by his travels including Ruines de la mosquée El-Hakem au Caire, said to have captured the monumentality of the ruins and the romanticism of the location. Theophile Gautier was deeply moved by his Place de l’Esbekieh au Caire, remarking: "On seeing this painting, I became sick at heart, and yearned for the Orient, in which I had not yet set foot." At the Salon of 1844, his Souvenir des bords du Nil was praised, as was Arabes syriens en voyage, now in the Musée Condé, Chantilly.

Marilhat's work falls into three periods: his early traditional landscapes and portraits, the drawings and sketches during his travels to the Orient, and his paintings after 1838 which, in addition to his well-received oriental works also included mythological subjects. Suffering from syphilis, Prosper Marilhat became insane and died in a Paris asylum in September 1847, only 36 years old.