A couple from Barry had hundreds of pounds worth of Christmas vouchers from their hotel room in Cardiff after it was broken into along with several others.
39-year-old Laura Carey and her 41-year-old fiancé Matthew Ford were staying in The Citrus Hotel on Tuesday for an event at the Cardiff Motorpoint Arena.
When they returned to the hotel they realised some of their possessions had been stolen.
Ms Carey said hotel staff told her that 11 rooms has been broken into, with gadgets including iMacs and iPhones among the items taken.
Police said they are investigating reports of theft involving a number of rooms at the Citrus Hotel.
Ms Carey said she has had to spend her wedding savings to pay for Christmas.
"The big concern for me was the keys for our house and car were in the room and if they had taken my driving licence they would have had our address and my 17-year-old stepdaughter was at home."
A spokeswoman from South Wales Police said: "Police in Cardiff are investigating reports of thefts from a number of rooms at the Citrus Hotel on Bute Terrace.
"The thefts are all believed to have occurred during the afternoon of Tuesday, December 10, with cash and electronic equipment among the items reported stolen. Enquiries are ongoing."
A spokesman from Citrus Hotels declined to comment due to the ongoing police investigation.