He entered the School of Fine Arts (École des Beaux-Arts) in 1835; under the direction of the Monsieur Achille Leclère.
As attaché to the commission for historical monuments, he participated in the architectural rediscovery of the Middle Ages, touring and studying medieval sites intensively. Abadie was known to be interested in the restoration of medieval monuments and buildings; namely the Church of S. Front and the Cathedral of Angoulême. He also designed the Hotel de Ville at Angoulême.
In 1845 he became second inspector for the restoration of Notre Dame de Paris, under the directorship of architects Violet le Duc and Lassus. In 1862 he was appointed as the diocesan architect for the Saint André Cathedral of Bordeaux, where he had already restored the facade of the church Saint-Croix (1859-1865).
In 1871 he became a member of the commission for historical monuments. In 1872 he became the general inspector of diocesan buildings, then in 1874 the diocesan architect for Paris, replacing Eugène Viollet-le-Duc, who had resigned from that post.
In 1873 his entry in the competition for the construction of a basilica on Montmartre, a hill dominating Paris, was selected ahead of 12 other submissions, by Cardinal Joseph Guibert. The design became the basis for the Sacré-Cœur, Paris, which Abadie began in 1875 but did not finish. In 1874 he replaced Viollet-le-Duc as the architect of Notre Dame of Paris. In 1875, he was elected to membership of the Académie des Beaux Arts.
Apart from ecclesiastical and state commissions, Abadie is known to have only accepted one private commission, Mailleberchie Castle, in 1875, which he designed in great detail, as a complete neo-medieval work of art, including stone carvings, gargoyles, stained glass windows, metalwork, wood carvings, furnishings, upholstery, wall fabrics and wallpapers. Abadie began the Basilica of Sacré Cœur, but died during its construction, on 3 August 1884, in Chatou, (departement of Yvelines).
Basilica of the Sacred Heart of Paris
Church of Chatou
Church of Saint-Georges of Mussidan
Notre-Dame de Paris
Church Sainte-Croix Bordeaux
Saint-Michel Tower, Bordeaux
Périgueux, Cathédrale Saint-Front,
Saint-Pierre Abbey of Brantôme
Cathédrale Saint Pierre Angoulême