The Romanian Patriarchal Cathedral, also known as the Patriarchal Cathedral of Saint Mary, is a Romanian Orthodox cathedral located in Bucharest, Romania. It is the most important religious landmark in the country and the seat of the Romanian Orthodox Church.

The cathedral was built between 1654 and 1658 by order of Prince Constantin Serban Cantacuzino, replacing an older church from the 16th century. The building was enlarged and modified several times throughout the centuries, the most notable renovation being undertaken in the early 20th century, when the current neo-Byzantine style was adopted.

The cathedral has a central dome flanked by four smaller ones, a typical feature of Byzantine architecture. The interior is decorated with beautiful frescoes, mosaics, and stained-glass windows. The cathedral also houses the tombs of several patriarchs of the Romanian Orthodox Church, as well as an impressive collection of religious art and artifacts.

The Romanian Patriarchal Cathedral is an important pilgrimage site for Romanian Orthodox Christians and a popular tourist attraction in Bucharest. Visitors can attend religious services, admire the beautiful architecture and art, and learn about the history and traditions of the Romanian Orthodox Church.