Ammar Daghmaj, 32, "was freed on the road 25km west of Kirkuk and only five kilometres from a police checkpoint", Lieutenant Colonel Abd Al-Karim Khalaf Jabburi said on Friday.
Daghmaj said he had been released by his captors after they determined that he was not working for the US army, Jabburi said.
He also passed on a message from his abductors saying they wanted to express their "appreciation for Syria's stance in supporting the Iraqi people".
Daghmaj was seized from a three-vehicle convoy near the village of Ismail Awa, police said on Thursday.
The convoy was transporting foodstuff from Iraq's northern oil capital of Kirkuk to the city of Mosul, further north.
Anti-US fighters regard foreign
truck drivers as collaborators
Truck drivers have been a frequent target of abductions in northern Iraq, most of them Turks.
On Thursday, a Jordanian driver Turki al-Braizat was released from captivity.
Al-Braizat "is now in the Jordanian embassy in Baghdad", a spokesman for the Foreign Ministry said.
"Al-Breizat's release was the fruit of intensive efforts carried out by the Foreign Ministry in coordination with our embassy in Baghdad, and the efforts of the noble residents and elders of Falluja," the spokesman added.
He did not elaborate.
The announced release came a day after al-Braizat's Jordanian employer said he halted commercial activity with Iraq in response to an ultimatum issued by the driver's captors.