McCarthy's men confounded the critics to earn a second season of top-flight football last season - and they made a good start to the 2010-11 campaign last weekend with a 2-1 defeat of Stoke at Molineux.
Wolves face Everton at Goodison Park on Saturday afternoon and McCarthy believes his men can have the belief they can make the right impression against the Premier League's top teams.
"It's your own self-belief as a player," he said.
"You look around at your team-mates and think 'we've got a decent team here'.
"That helps you not to worry about opposition and maybe helps you not think about it when you're playing at Everton or playing at Manchester United.
"Actually we've got a decent side. At least we've got players who have played in the Premier League and know they can play in the Premier League.
"We've got that. It doesn't guarantee us anything but at least we've got a bit of experience and understanding."
The Toffees started the season with a 1-0 defeat at Blackburn - but McCarthy is not reading too much into the result.
He continued: "They're still competitors for the top four.
"I don't think (manager) David (Moyes) has got loads of money to spend but they've got a really good squad of players.
"When they were all fit and they came here last season, they were as good a team as anybody we'd played. They were powerful, quick, athletic and good footballers.
"We fashioned a 0-0 draw out of it but that was a really tough game.
"I know they lost on Saturday, and I'm not big on statistics, but I saw them in terms of shots and corners and free-kicks - they seemed to be way in their favour, yet they were beaten 1-0.
"I know it (the goal) was a mistake, but I don't read too much into that.
"It's their first home game and they'll be buzzing. They'll be looking forward to us coming."