Gugliotto Amadeo (circa XVI century), erected during the Sforza phase of the construction of the Duomo of Milan by the architect Giovanni Amadeo, is positioned in correspondence of one of four pillars of the tiburium that supports the greatest spire. The present restoration intervention is part of the plan of continuous conservation of the Duomo of Milano. The state of conservation of the spire is conditioned by the particular exposure to atmospheric agents that, above all in correspondence of the ornaments, of the statues, of the pinnacles and of the most projecting decorations, denounced crackings and disintegrations of the stone matrix with total or partial loss of the volumetric plasticity of the artifacts. In general, the main ongoing restoration operations are of preconsolidation, cleaning, biocidal treatment, consolidation, plastering, final protection of the marmorean surfaces.