Erdogan first addressed local residents at a mass meeting, Today's Zaman reported.
He talked of the town's role in giving shelter to about 25,000 Syrian refugees living there.
"I believe that Reyhanli residents will embrace them," he said.
The May 11 bomb attacks killed 51 people. The Turkish government has blamed forces fighting for President Bashar Assad in Syria, but the Damascus regime denies carrying out the bombings.
Erdogan said Syrian refugees will return to their homeland once Assad has been ousted and the civil war is over.
After the public meeting, he met privately with the families affected by the bombings.