The Tottenham Hotspur Supporters' Trust claims the atmosphere at the stadium has "declined" as a result of some fans being "priced out of attending".
With just three wins from 15 Premier League home games in 2025, Spurs have struggled for results in front of their own supporters at the 62,850-seater stadium.
Despite their Europa League success last term securing them a place in the Champions League this season, the club's return to Europe's top tier has not brought bumper crowds, with numbers of 54,755 and 49,565 for home fixtures against Villarreal and Copenhagen.
The fan group said: "Over the past couple of seasons, it's undeniable that the atmosphere has declined at Tottenham Hotspur Stadium.
"Too many empty seats and too many supporters, particularly young supporters, priced out of attending. Thin the crowd and you thin the noise.
"Europa League nights last season, with sensibly priced tickets, proved the point: fair ticket pricing fills the ground, often with the next generation of Spurs fans. And the noise follows.
"The Champions League - our flagship nights - has seen thousands of empty seats, in our view due to unrealistic and unaffordable match pricing.
"A world-class stadium without a full house is only half a home."
Tottenham recently announced the visit of Borussia Dortmund in January will now have category B pricing instead of category A, and ticket prices for this season were set in the summer when Daniel Levy was still chairman.