Duke of Porto (Portuguese Duque do Porto) is a title of Portuguese nobility, held by members of the royal family.

It is named for the city of Porto, in the north of Portugal.

The title's name was made in honour of the city of Porto, due its loyalty to Pedro IV and Maria II in the Liberal Wars.

Following the use of the title by Maria, Princess Royal of Portugal, the title became associated with the second male child of the head of the Royal House of Portugal.

After the end of the monarchy, the following individuals have claimed the title of Duke of Porto: