The frontier was closed after the blasts took place on Monday.
The Bab al-Hawa crossing is held by the so-called Islamic Front militants, which have been fighting with the al Qaeda-linked Islamic State in Iraq and the Lavent (ISIS).
It was not immediately clear who planted the bombs.
The attack occurred a few days after a car bomb that killed 26 in the eastern city of Jarablus and which activists blamed on ISIS terrorist group.
The infighting between militant groups has sparked the bloodiest internecine clashes in the history of Syria's nearly 3-year-old war.
A Syrian activist at Bab al-Hawa said that the two car bombs exploded within 10 minutes of each other.
The governor's office in neighbouring Turkish Hatay province said the explosion was on the Syrian side of the border.
Its press spokesman Cahit Dogan said there were no reports of damage or injuries on the Turkish side.
RA/NJF