The Union of Students in Ireland has warned students looking for accommodation to be on the look-out for scammers.
The union said fraudsters were advertising properties and seeking payment online for rooms which either don't exist or are not for rent.
The union is appealing to families to rent out spare rooms because of the severe shortage of suitable accommodation in urban areas.
The USI's vice president for welfare Greg O'Donoghue advised students to do their research and ring the landlord in advance and ask to see the house.
"They need to see that it's adequate accommodation," he said.