The ministry said the bombing, which it blamed on the Kurdish YPG militia, took place southeast of the Syrian town of Tel Abyad which Turkey captured in a military offensive that began one month ago.
Turkey halted its military advance when it struck deals with the United States and Russia calling for the YPG to be moved at least 30 km (20 miles) away from Syria's border with Turkey.
The village of Suluk, where Sunday's explosion took place, is around 10 km south of the border. A small truck exploded outside a bakery there, an emergency worker said.
Turkish soldiers and Syrian rebel fighters launched the incursion to clear the border region of the YPG, which Ankara has designated a terrorist group because of its ties to Kurdish militants waging an insurgency in southeast Turkey.
The offensive faced international criticism over fears that it could undermine efforts to prevent Islamic State re-emerging in Syria and unleash another humanitarian crisis in Syria's eight-year conflict.
The YPG was the lead force in the Syrian Democratic Forces, Washington's main ally in the battle against Islamic State in Syria. U.S. President Donald Trump has faced domestic criticism for announcing a troop withdrawal which was seen as a green light for Turkey's incursion.
Erdogan has said both Moscow and Washington have failed to meet their commitments under last month's agreements for the YPG to withdraw from the border, and has said Turkey could resume its offensive if terms are not adhered to.He spoke to Russian President Vladimir Putin by phone on Saturday, and is due to meet Trump in Washington on Wednesday.