The Church, being declared National Monument in February 1982, dates from the 18th century although it acquired its definitive structure between 1799 and 1804. During this period it suffered one of its major redesigning.
Once Bullas achieved the political division from Cehegín, in 1689 Charles II of Spain granted to Bullas the privileged status of royal borough, and then the municipality also aspired to religious independency. According to several studies, the first building work was conducted by Francisco Bastida and Francisco Muñoz. The Church was unveiled on 8 December 1723, feast of the Immaculate Conception. The name 'Our Lady of the Rosary' was adopted through popular vote with overwhelming majority.
In the late 18th century a restoration was conducted under surveillance of Jerónimo Martínez de Lara. The Church would display a similar layout to that it shows today: Latin Cross ground plan of three naves with crossing and a central dome on scallops. The difference between the original structure and that which has survived till our times is primarily the location of the sacristy, as firstly it was located where the chapel of the Sacred Heart lies in these days.
The central nave is covered by barrel vaults with transverse arches and the lateral naves, by groin vaults. The influence of Martínez de Lara has remained visible in the tower and the sacristy with clear neoclassical influence. The decoration of the chapel of the Sacred Heart, also built in the early 19th century, is based in neo-Gothic elements, typical of the period when it was built.