The Capture of Porto took place in October 1580 by the Spanish forces commanded by Don Sancho d'Avila during the War of the Portuguese Succession.

The city was captured easily by the Spanish troops, thereby finishing off the Prior of Crato's army and its final defeat in Mainland Portugal, thus assuring the personal union of Portugal and Spain for 60 years under the Iberian Union.

Following the victory accomplished by the Spanish troops led by Don Fernando Álvarez de Toledo, Duke of Alba at the Battle of Alcântara on 25 August 1580, near Lisbon, the decimated Portuguese army under the command of Dom António, Prior of Crato, fled towards Coimbra and Porto with the intention of reassembling his troops.

The Spanish troops commanded by Don Sancho d'Avila, transported by sea, arrived and disembarked in Porto on 24 October 1580.

In early 1581, Dom António fled to France carrying with him the Portuguese Crown Jewels, including many valuable diamonds.