The Church of San Leonardo di Masullas was built in the first half of the 12th century and is made entirely of tuff sandstone blocks. The building has a simple but harmonious layout, characterised by a single large nave leading to the apse and a sloping façade surmounted by a bell gable.

During restoration work carried out in 1977, traces of the foundations of a previous single-nave hall were discovered, on which the Romanesque church was later built. The current building has retained its original orientation, with the longitudinal axis and apse facing north-east.

From a construction point of view, the two main façades are made of sandstone and trachyte blocks, while the sides feature a mixed stone facing. The facade is embellished by a recessed false loggia, bordered by double-ring arches and a scarp that is interrupted at the two half-columns, giving the whole an elegant architectural balance typical of the local Romanesque style.