The Euphrasian Basilica (Croatian: Eufrazijeva bazilika, Italian: Basilica Eufrasiana) or the Cathedral Basilica of the Assumption of Mary is a basilica in Poreč, Croatia. The episcopal complex, including, apart the basilica itself, a sacristy, a baptistery and the bell tower of the nearby archbishop's palace, is one of the best examples of early Byzantine architecture in the Mediterranean region.
The Euphrasian basilica has for the most part retained its original shape, but accidents, fires and earthquakes have altered a few details. Since it is the third church to be built on the same site, it conceals previous buildings, for example the great floor mosaic of the previous basilica from the 5th century. Because of its exceptional value, it has been inscribed on the UNESCO World Heritage Listsince 1997. The Basilica is also the Cathedral of the Roman Catholic Diocese of Poreč-Pula.