Levein hinted that McFadden has not been pulling his weight at international level and that is why some managers have omitted him in the past.
However, McFadden put in a decent shift in Sunday's goalless draw with Liverpool and McLeish insists the 27-year-old is one of the hardest workers at the club.
Former Scotland head coach McLeish knows McFadden better than most and insists the striker would never give anything less than his best for his country.
"I've worked with James for a long time now and he is actually one of the best trainers at the club," said McLeish.
"I can show you James' figures and they are way up there in terms of sports science. If anything he probably does too much in training.
"I don't think there should be any aspersions cast against James. He would walk over hot coals to play for Scotland.
"The last year has been typical James McFadden. He has been mercurial for Scotland, a real talisman and the Tartan Army love him - and he loves them back.
"James deserves respect and I am sure him and Craig will go on to have a good relationship.
"I am not going to take Craig Levein to task because he has criticised one of my players.
"I will continue to manage players my way and Craig has got to do it his way."