Piazza Yenne, Central square in Stampace district, Cagliari, Italy.

Piazza Yenne is an oval-shaped pedestrian square at the end of Largo Carlo Felice in the Stampace district. Its current layout dates from a 1980 restoration that reused pre-existing elements and made the area pedestrian-only. A bronze and granite sculpture by Carlo Loi stands at one vertex of the oval, facing the milestone column at the opposite vertex.

The first stone was laid in 1822 under the name Piazza San Carlo, honouring King Carlo Felice of Sardinia. In the second half of the century it was renamed for the viceroy Marquis Ettore Veuillet d'Yenne, who had wanted it built. A 1980 restoration made it pedestrian, and in 2017 the central fountain and Carlo Loi's sculpture were removed.

The square's name honours Marquis Ettore Veuillet d'Yenne, the viceroy who ordered its construction; the earlier name San Carlo referred to King Carlo Felice. The bronze and granite sculpture by Carlo Loi stood at one corner of the oval until the 2017 restoration removed it along with the central fountain.

The 2017 restoration cleared the central fountain and Carlo Loi's sculpture, leaving a wide open pedestrian space in the middle. Commercial seating was reorganised with smaller volumes, favouring tables and umbrellas over the earlier gazebos. The square sits at the end of Largo Carlo Felice, in the Stampace district.

The square marks the exact starting point of the SS131, the main highway that runs across the entire island of Sardinia from south to north. This major route begins precisely at this location, connecting Cagliari to the rest of the island.