Operator ScotRail and the National Union of Rail, Maritime and Transport Workers (RMT) met this morning but attempts to find a resolution failed.
RMT members at Scotrail are due to strike on December 22 and Christmas Eve.
The action is in support of former ticket inspector Scott Lewis who was dismissed after an incident over the type of ticket used by a member of the public.
Scotrail describes the industrial action as a "clear attack" on the travelling public at Christmas.
RMT members on the firm's sleeper services will also strike for 24 hours from the evening of December 21 and again from the evening of December 23.
A ScotRail spokesman said: "It is extremely disappointing that the talks failed to reach a solution. The RMT wanted the former ticket examiner to be reinstated."
Contingency plans aim to keep any impact on travellers to a minimum, the spokesman said.
"There is no doubt that the majority of our services will run," he continued. "As always, we are available for further meaningful talks at any time."
RMT members voted last month by 2-1 in favour of industrial action, while the dispute has remained deadlocked.
The union said Mr Lewis was trying to make sure the passenger had the correct ticket and was dismissed for making "unwanted contact" with the man.
General secretary Bob Crow called for the worker's immediate reinstatement.
"Scott Lewis has been victimised and sacked for trying to help a passenger within the written procedures set out in ScotRail's own policies in what is an absolute travesty of justice," he said.
After the talks, Mr Crow said: "RMT arrived at the talks today only to find that ScotRail were not prepared to discuss the issue at the heart of the dispute and that's the dismissal and reinstatement of Scott Lewis.
"We have been led up the garden path by the company who had no intention of entering into meaningful discussions and as a result of ScotRail's actions the strike remains on."