Two suicide car bombs have killed 50 people in Iraq, marring celebrations as football fans cheered their country's win in the Asian Cup.

Police said a suicide car bomb exploded near a crowd of jubilant Iraqis, killing 30 and wounding 75 in Baghdad's Mansour area.

Another suicide attack struck soon after at an army checkpoint in east Baghdad, killing another 20 people and wounding 60, many of them football fans celebrating nearby, police said.

The bombings were a sharp reminder of the sectarian violence between deeply divided Shia Muslims and minority Sunni Arabs that has killed tens of thousands.

In Sadr City, a sprawling Shia slum in Baghdad, women threw sweets to dancing football fans with Iraqi flags draped over their shoulders.

Some families sacrificed sheep as celebrations dragged on into the evening.

The celebrations began moments after Iraq beat South Korea in a dramatic semi-final penalty shootout to reach the Asian Cup final for the first time.