"The Church does not bless the frenzy and psychosis that a person falls into when they watch these games," Filaret, head of the Ukrainian Orthodox Church - Kiev Patriarchate, was quoted as saying by UNIAN news agency.
Filaret, whose branch of the Ukrainian Orthodox church has up to 10 million followers, said his church supported sports and healthy lifestyle in general.
"Just look at these people's faces," he said. "They are no longer human, they look more like monkeys than humans. That's because they lose [emotional] balance.
"It is a sinful state when a man does not control himself. That is when they drink and fight. We are against that," The 83-year-old cleric said.
Ukraine is co-hosting the European Championship with Poland at a time when Orthodox Christians are supposed to observe the Fast of the Holy Apostles and show emotional restraint.
Filaret said he was not following the games or rooting for the national team who will play a decisive group match against England on Tuesday.
"I have nothing to do with football ... thus I do not support football [teams] but I support Ukraine. Football means nothing at all to me but I am paying attention to what it means for Ukraine," he said.
Filaret's stance contrasted sharply with the position of the Polish Catholic Church which has been welcoming fans and arranging special masses.
Cardinal Stanislaw Dziwisz, the Archbishop of Krakow, blogged excitedly about Poland's first game, revealing he prayed for their keeper Przemyslaw Tyton, who made a stunning penalty save in their opening 1-1 draw with Greece.
The Church's backing, however, did not help the co-hosts to qualify from their group after a surprise loss to the Czech Republic last Saturday.
