Bachir Khodr, governor of the Baalbek governorate where Arsal is situated, said the fire had affected four tents in the Al Shafaq neighbourhood and had since been extinguished. Lebanon's civil defence, which carries out firefighting operations, said it had put out fires in five tents.
The cause of the fire was unknown, but Mr Khodr urged people to follow public safety guidelines.
Footage shared online showed tents on fire.
The Lebanon mission of Doctors Without Borders (MSF) was among those to provide emergency medical assistance at the scene.
“We are very saddened by the death of two people in the incident”, said Marcelo Fernandez, the MSF head of mission in Lebanon.
“Upon their arrival, our medical team provided emergency medical care to four individuals who suffered mild injuries during the incident as well as mental and psychological assistance to those affected and their families.”
On top of a hill in the Anti-Lebanon Mountains, winters can particularly bleak in Arsal, a largely Sunni Muslim town in the north-eastern reaches of the governorate.
Many Syrian refugees live in grim conditions in informal settlements in Arsal. With poor sanitary conditions, it was one of the places where a cholera outbreak took hold last year.
Lebanon hosts more than a million Syrian refugees, who have fled the more than a decade long civil war in their country.