The study of architectural elements from Beauvais during antiquity, led in the context of preventive archaeology but also incorporating former archaeological interventions, has revealed the remains of polychromy on around fifty blocks or lots. This article presents a catalogue of these limestone blocks, including drawings and microscopic observations of the colours. While the presence of paint on ancient architectural features is not surprising, its state of preservation and the presence of green and blue pigments is remarkable. The corpus shows that the architectural ornamentation is rich, with for example the cross-decorated columns. In addition, the panels from the Hôtel-Dieu site show that the desire to imitate marble on a limestone base is confirmed before the 2nd century AD. These blocks therefore offer prospects for physico-chemical studies that would add to the information on the supply of resources and trade networks in Beauvais during Antiquity.