Uefa's allocation for wheelchair users at the Champions League final "is bordering on exclusion and discrimination", says the Liverpool Disabled Supporters Association (LDSA).
Liverpool will play Real Madrid in Saturday's game at the Stade de France, which has 550 wheelchair user spaces.
Uefa says it has provided 93 wheelchair positions for the match, with each team getting 38.
"We're really angry about it," said Ted Morris, secretary of the LDSA.
Level Playing Field - a campaign group for disabled sports fans - has written to Uefa to ask about the issue.
The final is to be played in Paris after St Petersburg in Russia was stripped of the match following the nation's invasion of Ukraine.
"For an event of this size, Uefa would usually aim to identify a higher number of [wheelchair] positions, but due to operational constraints (e.g. security, poor view, etc.) and the short preparation time, it was not possible to implement optimal solutions for more wheelchair positions," said European football's governing body.
Morris said he will be going to the game with a "tinge of sadness" because of the situation.
"It's not fair when bays are available. It is just wrong," he said.
"I'd like Uefa to clarify what they are being used for. This affects both teams."
Liverpool are believed to have contacted Uefa three weeks ago to request more tickets for disabled supporters but were told there were no more available.
The club are also waiting on Uefa to get back to them after asking this week if there are any returns or if more become available.
Morris added: "Liverpool have done everything in their power to help with this."
Michael Corness' 10-year-old son Harry is a wheelchair user and Liverpool fan and missed out on a ticket to the final.
"Based on the law of averages, you are assuming that you are going to get a decent allocation of wheelchair spaces," Michael Corness told BBC Radio 5 Live.
"I pre-booked the flights, hoping that we would be successful as Harry met the criteria of the ballot allocation based on the Champions League group games.
"I was absolutely shocked and so disheartened because I knew that based on the 38 spaces, it was going to be such a long shot to be successful.
"I was still hopeful as we did have a chance but at the back of my mind I knew it was going to be such a long shot."
Overall, Liverpool and Real Madrid have each received 19,618 tickets for the game, which has a capacity of 75,000.
A further 12,000 tickets were put on general sale via a ballot, which closed before the semi-final second legs were played.
Uefa president Aleksander Ceferin said the distribution and pricing of Champions League final tickets is "the system that works" as it aids clubs.
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