St. Joseph Co-Cathedral, Catholic cathedral in Thibodaux, United States.

St. Joseph Co-Cathedral is a Renaissance Revival church with pressed brick walls, stone trim, twin towers flanking a rose window, and a terra cotta tile roof. Its 34-foot baldachin in the apse carries symbols of the Four Evangelists, and the dome shows the Tree of Life, a snake, an apple, and peacocks. The building serves as co-cathedral of the Diocese of Houma-Thibodaux.

St. Joseph Parish organized in 1813 and was founded in 1817 as a mission to Assumption Church in Plattenville. A small wooden church was built two years later near the current cemetery. In 1849 Rev. Charles Menard had a brick church built, which a fire destroyed in 1916. The present church was begun in 1920 under Msgr. Alexander Barbier and completed in 1923.

The parish takes its name from Saint Joseph, and its symbols fill the church: the Four Evangelists are carved on the 34-foot baldachin and repeated on the columns, above casts of grapes and wheat for the Eucharist. The dome carries the Tree of Life, a snake, an apple and peacocks, with the coats of arms of Pope Pius XI and Archbishop John Shaw of New Orleans.

The building is open to visitors and located in downtown Thibodaux, easily accessible on foot. The best time to visit is outside of Mass times, when the interior is quieter and architectural details are more visible.

Inside the building sits a glass sarcophagus holding the relics of Saint Valerie, which survived the 1916 fire. These sacred remains stand as a rare testament to the site's spiritual heritage and attract pilgrims exploring the place's religious history.