The 16-year-old native of Hawaii has accepted an exemption to play in the Sept. 7-10 event in Switzerland -- her first on the European men's tour -- and is also attempting to qualify for this year's U.S. Open.
'She's got to prove herself that she can win on the women's tour before she can even have a chance on the men's tour,' Campbell said Wednesday on the eve of the Irish Open.
Wie has played in eight men's events and made her first cut earlier this month in a tournament in South Korea.
Campbell, who defends his U.S. Open title at Winged Foot, N.Y., next month, suggested Wie should focus first on winning a women's event.
'Michelle Wie is obviously a wonderful talent,' he said. 'She hits it as long as the guys. But she needs to prove to herself -- more so than to anybody else -- that she can win on the ladies' tour before she can come out and actually make a cut on the U.S. Tour or the European Tour.
'She's come close a few times and made a cut over in Korea, but obviously the quality of the field isn't as strong,' he added.
Since one of Wie's sponsors, watchmaker Omega, is also the sponsor of the Swiss tournament, Campbell said it was understandable she would be invited. But he said including her would deprive a man of a spot.
'It's up to the sponsors and good luck to them,' Campbell said. 'It's more viable for them to send over Michelle Wie commercially. But in this game, it's not all about making money. It's all about having fun rather than making money all the time.'