The Port of Barcelona (Spanish: Puerto de Barcelona / Port de Barcelona) has a 2000-year history and a great contemporary commercial importance. The port is managed by the Port Authority of Barcelona. Its 7.86 km2 (3 sq mi) are divided into three zones: Port Vell (the Old Port), the commercial port and the logistics port (Barcelona Free Port). The port is undergoing an enlargement that will double its size thanks to diverting the mouth of the Llobregat river 2 km (1¼ mi) to the south.

The Port Vell area also houses the Maremagnum (a commercial mall), a multiplex cinema, the IMAX Port Vell and Europe's largest aquarium, containing 8,000 fish and 11 sharks contained in 22 basins filled with 6 million litres of sea water. The Maremagnum, due to being situated a designated tourist zone, is the only commercial mall in the city that can open on Sundays and public holidays.

The Barcelona Free Port or Zona Franca de Barcelona is a tariff-free industrial park that has developed within the Port of Barcelona, across the flat land of the Llobregat delta between the city of Barcelona and Barcelona International Airport to the south.