Louis-Pierre Baltard (9 July 1764, Paris – 22 January 1846, Lyons) was a French architect, and engraver, born in Paris. He was originally a landscape painter, but in his travels through Italy was struck with the beauty of the Italian buildings, and changed his profession, devoting himself to architecture.
In his new occupation he achieved great success, and was selected to prepare the plans for some of the largest public edifices in Paris. His reputation is chiefly based on his skill in engraving. Among the best known of his plates are the drawings of Paris (Paris et ses monuments, 1803), the engravings for Denon's Égypte, the illustrations of Napoleon's wars (La Colonne de la grande armée), and those contained in the series entitled the Grand prix de l'architecture, which for some time he carried on alone. He also gained distinction as an engraver of portraits.
Two of his children were also architects. Of these the more important was Victor Baltard.
Louis-Pierre Baltard and Jean-Baptiste Rondelet were candidates in the competition to transform the Panthéon de Paris into the « temple de la Gloire ». In 1813, on the death of Alexandre Théodore Brongniart, Baltard proposed to undertake the building of the Palais Brongniart, but was unsuccessful.