The last time Canada didn't win the tournament was 1995.
"We've had success and that's great," said Barr, head coach and GM of the Ontario Hockey League's Guelph Storm. "There's a little extra pressure on Canada all the time because we are expected to be successful.
"I'm looking forward to the pressure that will be thrust upon us."
Barr, who had a 13-year NHL career with six teams, was the OHL's coach of the year in 2006.
Rounding out the under-18 team's coaching staff will be assistants Guy Boucher of the Drummondville Voltigeurs and Jacques Beaulieu of the Saint John Sea Dogs, both of the QMJHL.
The Aug. 14-18 tournament, which used to be known as the Junior World Cup, will be played in the Czech Republic and Slovakia.
Teams from the Czech Republic, Finland, Russia, Slovakia, Sweden, Switzerland and the U.S. will also compete at the event.
The tournament is often the first international competition for young players. Many of the players on the under-18 team go on to represent Canada at the world junior championships.
"It's going to be very important for us to get the players to be thinking about what we need to do to have success right away," said Barr. "They have to adjust to the different size ice and adjust to the different type of game.
"That's our job as a coaching staff is to prepare them right away so when we get into a game situation they are not feeling their way through it anymore."
Barr has attended the under-18 championships in the past to scout players but has never coached internationally. He doesn't expect it to be much different than coaching in the OHL.
"You lay your systems out for your players and you work with the players individually getting them ready," he said. "Much of it is preparing them for the game and putting them in the best position to perform."