Église Notre-Dame-de-Bon-Secours, Catholic church in Trouville-sur-Mer, France

Église Notre-Dame-de-Bon-Secours rises in pale tan masonry above a crimson round-arched double door, with a large rose window in carved stone tracery, a row of three arched openings between pilasters and a steep slate roof topped by a dark lantern. Its high facade stacks columned registers; the interior has a compact plan without a projecting transept, coloured stained-glass lancets and oculi, a stone dolphin supporting a giant bronze-edged tridacna shell as holy-water stoup, an 1880 pulpit and troubadour-style confessionals.

Abbot Jean Vincent Lessard had a chapel built here in 1844; Hennequeville accepted its donation on 14 January 1845. The town architect Adrien Jory proposed a new building in 1867-1868, of which only the pediment was built. From 1872 to 1884, under contractor Belloc and architect Toutain, side chapels were added, giving the trapezoidal plan; Bishop Hugonin dedicated it on 27 July 1884 and Bishop Amette consecrated it on 4 August 1900.

The church keeps 18 listed objects, among them a 15th-century tapestry, La flagellation du Christ, and a confessional bearing coats of arms. Its own arms, topped by the Virgin's crown, appear on both sides of the nave and on the confessional pediment, with the motto "Ad quam confugimus in auxilium" on a scroll beneath the shield.

The building has been closed to the public since 2018 due to structural concerns requiring safety measures, and the municipal council initiated conversion procedures in 2023. Visitors can view the exterior of the building, and information about its planned future use may be available from local tourism facilities.

The organ case was built by Charles Mutin in 1893 and won a gold medal at the Lyon International Exhibition before the parish bought it in December 1894; it was inaugurated in August 1895 and fully restored in 2004. Its neo-Gothic buffet is listed as a monument historique.