The Church of the Holy Trinity in Mława is a Roman Catholic parish church located in the Płock diocese, playing a significant role both in the religious and historical life of the local community. Its history dates back to 1477, when it was built as a single-nave, late-Gothic structure with a protruding chancel. Over the centuries, the church endured numerous fires, the most severe of which occurred in 1692, after which it was rebuilt. Between 1882 and 1886, it underwent major renovations that gave it a Neo-Baroque style, often also referred to as Tuscan or Old Romanesque. Although the architecture of the church lacks original historic features, it retains traces of its earlier construction, such as the rood screen and a fragment of a window in the chancel. After the reconstruction, two side aisles and a new front facade with tall towers were added. While these towers are not organically integrated with the rest of the structure, they reflect the architectural tastes of the time, drawing inspiration from the style of Orthodox churches. The church has not only served a sacred function but has also become a symbol of local culture and history. Its repeated reconstructions stand as a testament to the continuity of social life in Mława.