Fabio Capello's side need only a draw to guarantee qualification, with the hosts having to win to have a chance of beating the Three Lions to top spot in Group G
The Three Lions will top Group G provided they don't lose against their hosts, and the Manchester City midfielder hopes an unbeaten qualifying campaign will stand the side in good stead for next summer's tournament in Poland and Ukraine, but he warned against complacency by pointing to the nation's poor performances at the 2010 World Cup.
"If we can get a victory, the confidence going into the European Championships will be higher," he told BBC Sport.
"We qualified in great style for the World Cup and our performances there weren't brilliant. Hopefully our performance in the European Championships can be better.
"It's a massive game. When the fixtures came out we knew Montenegro away was going to be a tough fixture.
"We know it's going to be tough. They kept us out at Wembley and will be up for it in their home city. But we go there confident."
England won nine of their 10 qualifiers for the 2010 World Cup but were poor in South Africa last summer, and Barry believes the experience could benefit the team.
"If games don't go to plan that's what can happen but you don't have to worry about it or it affects your performance," he said.
"You can never take your place for granted. If you are not performing at a high level you expect criticism and someone is there to take your place.
"I'm sure there are a few from the World Cup who can help us when we travel to the European Championships."