The criticism, from Martin Kallen, UEFA's director of the championship Poland will stage with Ukraine in 14 months' time, comes days after the latest hooligan outbreak when Polish fans wreaked havoc at a friendly with Lithuania in Kaunas on Friday.
Kallen, organising his fifth European Championship for UEFA, said none had caused as many problems as this tournament and was highly critical of Poland's football image.
He also said some projects in Ukraine, including motorway construction, would not be ready despite plans adopted in 2008.
Kallen told delegates at the Soccerex European business forum there were now outbreaks of hooliganism at just about every league match in Poland.
More than 60 Polish fans were detained after throwing bottles, flares and benches at police in Lithuania last week - an attack which has been condemned by the Polish government.
Police had to use tear-gas and dogs to control the rioting fans against several hundred Polish fans, who also threw stones and bottles outside the Darius and Girenas stadium in Kaunas before and during the match which Poland lost 2-0.
NEW LAWS
The Polish government has also announced new legislation to tackle football violence similar to the laws brought in by Germany for the 2006 World Cup.
Kallen said: "We are concerned but I know the Polish government is also concerned but we are not going to let a minority spoil it for the majority.
"They know they have a huge image problem, there are always hooligans around every match day in the league but the government is making the right steps for the future.
"What we saw at last Friday's match was not a very good picture to see that happening in a stadium. We and the Polish government are concerned, they are taking this seriously and will have changes in the next month."
Kallen said he was convinced the championship would be a celebration and was not too concerned about trouble at the tournament itself as the problem was more linked to club matches.
He added: "For the Euro, different people will be coming to matches -- there will be more families. The Euros are a party and in many areas there is more a problem on a daily basis for club matches. But, clearly, we are facing some challenges.
ZERO TOLERANCE
Marcin Herra, head of the Poland 2012 organisers, told delegates there would be "zero tolerance" for hooligans but he was quick to add that the championship would leave a lasting positive legacy for his country and Ukraine.
"We have new legislation which allows us to work much more precisely against those hooligans.
"There will be zero tolerance to make sure that 500 people cannot spoil the event for one million people."
Herra added that new laws will allow police to speed up the process of arresting suspected hooligans and dealing with them in court.
Fans also have to be part of a central database in order to buy
