Glastonbury organiser Michael Eavis has asked police to investigate whether forged tickets were sold for the event.
Michael Eavis was the founder of the festival
Mr Eavis has asked Avon and Somerset Police to investigate whether 500 tickets bought through an unnamed website were forgeries.
This year's festival was a sell-out, leaving many fans disappointed they could not get hold of tickets.
This led to a high-demand from unofficial sources, with tickets changing hands for up to £400.
"I am asking the police to find out where these tickets came from," said Mr Eavis.
"There is a serious problem here and I am not happy about the source of the tickets."
Mr Eavis reported the matter to police after an investigation by the BBC's Watchdog programme.
More than 100,000 tickets were sold for the festival held at Worthy Farm in Pilton, Somerset.
This year, organisers tried to stamp out ticket touting by limiting the amount each person was allowed to buy.
People who bought tickets had to provide proof of identification to match up with personal details printed on the tickets.
But this led to frustration as people continually tried to get through to telephone lines and a website ticketing agency, with technical difficulties being blamed for the problems.
Mr Eavis has promised to address the issue before tickets for next year's event go on sale.