Pierre Monier or Mosnier (17 May 1641 – 29 December 1703^[1]) was a French painter and author.

Mosnier was born in Blois. His father Jean Monier was also painter, and was his first teacher. In 1664 he won the inaugural Prix de Rome for his painting la Conquête de la Toison d’Or ("The Conquest of the Golden Fleece"). In 1665 he travelled to Rome to continue his studies at the School of Rome. He moved back and took up residence in Paris, where he fulfilled a number of commissions, primarily religious-themed works for churches, such as for the Saint-Sulpice, Paris.

On 6 October 1674, he accepted as an Academician for his painting Hercule se préparant à la défense de la ville de Thèbes, sa patrie, menacée par les Minyens, et recevant d’Apollon des flèches, de Mercure une épée et de Vulcain une cuirasse.

Mosnier later taught at the Académie de peinture et de sculpture. In 1698 he wrote and published a series of three books on art: History of the Arts Associated with Drawing. Monier continued to paint until his death in 1703. He died in Paris.^[1]