Organo della basilica di San Pietro in Vaticano, Pipe organ in St. Peter's Basilica, Vatican City

The Tamburini pipe organ in St. Peter's Basilica features 76 stops spread across four manual keyboards and a pedalboard. This instrument occupies significant space within the basilica's interior architecture and contributes substantially to the acoustics of the vast church.

The first documented organ in the old basilica appeared in the 14th century, with four instruments recorded by the 15th century. Following the basilica's reconstruction, the organ was renewed multiple times to serve evolving liturgical needs.

The basilica holds five pipe organs, not one: the main Tamburini instrument behind the choir pillars, two facing each other in the Choir Chapel (Morettini 1887, Tamburini 1974), the 1914 Morettini organ of the Sacrament Chapel, and a mobile Walcker organ given to John Paul II in 1985. Frescobaldi was appointed basilica organist in 1608, when three organs stood in the church.

The main organ stands in two halves behind the choir pillars, so it is heard best from the nave and transept rather than close to the apse. A three-manual radio console added by Mascioni in 2002 allows it to be played from elsewhere in the basilica. The two choir chapel organs face each other behind matching cases.

In 1875 Aristide Cavaillé-Coll designed a five-manual organ of 124 stops for the east wall, but Pius IX answered only "suspendimus organa nostra". A 1:10 model shown to Leo XIII in 1887 survives in a storeroom at the base of the dome. Charles Mutin's 1910 plan for 153 stops and 10,603 pipes raised 60,000 francs, later spent on the choir floor.