Iraq's Khor al-Zubair commodities port near Basra reopened on Wednesday and operations resumed normally, port officials said.
On Tuesday protesters blocked the entrance to the Gulf port and prevented trucks from entering, as part of the biggest wave of anti-government demonstrations in the country in decades.
Officials said they have been holding talks with protesters and finally managed to convince them to leave the entrance, which allowed the port to resume normal operations.
Khor al-Zubair is Iraq's second main Gulf port. It is used to export cargoes of gas condensates and receives refined oil product shipments, construction and electrical commodities and food.
Iraq's major commodities port of Umm Qasr is still closed after hundreds protesters on Monday again blocked the entrance to the port near Basra, preventing employees and tankers from entering and bringing operations to a complete halt.
Talks with protesters have not managed so far to make them evacuate Umm Qasr's entrance, port officials said.
At least 315 people have been killed since the start of mass unrest in Baghdad and southern Iraq in early October, the largest demonstrations since the fall of Saddam Hussein in 2003.
The protests are part of a movement that has brought tens of thousands of Iraqis to the streets to demonstrate against corruption and the poor state of public services.
Reporting by Aref Mohammed