The New Municipal Palace (building in Castellón de la Plana, province of Castellón, Valencian Community, Spain) is a Baroque-style administrative building built between the 17th and 18th centuries in the town's Plaza Mayor.

It is a free-standing structure with a rectangular ground plan and three floors, as well as a central staircase that leads to the various rooms. The façade is divided into three sections by horizontal bands in the shape of cornices. The ground floor features a portico with five semicircular arches alternated with Tuscan pilasters, with one on each side. The main floor is divided into five sections vertically by Corinthian pilasters and a plain entablature. It has three balconies, one of which is continuous, and five openings. The smaller third floor is separated from the rest of the building by an overhanging cornice and features five simple balconies flanked by pilasters. A balustrade surrounds the building.

The Assembly Hall was renovated in the first half of the nineteenth century, and the ceiling was decorated with an allegorical painting of Castellón de la Plana. The balcony on the main floor was replaced by a single balcony at the beginning of the twentieth century, and after the Spanish Civil War, the side and main façades were renovated, with the two corner towers and the parapet being replaced by the current balustrade.