Claudia Morel-Zifonte Palladino claimed venue suggestions of a restaurant or family-friendly farm were derided by younger colleagues who wanted to go to a venue in London.
She told an employment tribunal she had suffered a 'detriment' as a result.
However, her claim was dismissed by the tribunal judge, Robin Lewis, who ruled that simply being disagreed with is not discrimination or harassment.
The tribunal also dismissed Palladino's discrimination complaint that a colleague in her mid-20s had remarked to her that she had a lot of experience, saying that it was "factually correct".
Additional claims of victimisation and constructive dismissal will proceed to a full hearing and be heard at a later date.
Claire Brook, employment law partner at Aaron & Partners, said although Palladino claimed disputes with her colleagues were due to age, the tribunal found she could not prove this.
Speaking to HR magazine, she said: “The judge held that not every displeasing event at work amounts to a detriment and the claimant’s feelings alone are not evidence to make a case for discrimination.”
Simon Jones, director of HR consultancy Ariadne Associates, said the case is a reminder that having a protected characteristic does not mean you will win a case.
Speaking to HR magazine, he said: “This was an extremely weak claim. Having a protected characteristic, in this case age, and trying to claim anything you don’t like at work is discrimination because of it, is not likely to succeed.
“The Christmas party incident is a perfect example of this. The claimant suggested one venue. A group of staff who happened to be younger suggested another. The claimant tried to persuade others around her way of thinking and wouldn’t budge from her choice.
“The judge described this as a 'minor everyday workplace issue' which couldn’t possibly be considered a detriment on the grounds of age.”
However, Brook said businesses should make sure that work social events are inclusive and bring staff together.
She said: “Inclusivity remains important to build morale, trust, positive working culture and opportunity at work.
“Where employees are excluded from participation this can lead to mistrust, ‘quiet quitting’ and a feeling that there might be discriminatory intent or bias.
“In some circumstances, if there is evidence to suggest discrimination, this could give rise to successful claims.”