The Republic of Ireland international is a reported target for several Premier League clubs but McCarthy has dismissed talk of his exit and backed him to maintain the form which has seen him emerge as a key player for Wolves.
"Kevin is old enough to realise that speculation counts for nothing," McCarthy said.
"It makes for good reading in the summer when there is nothing else to write about.
"But he continues doing his job and nothing fazes him.
"He's a great character and been one of our top dogs for the past two years."
McCarthy believes the Wolves players have a responsibility to ease the pressure on Doyle, who often operates as a lone striker.
He said: "He plays up front on his own and, when he was out injured, you could see how much we missed him.
"I don't see why he can't get better - if we get better and provide him with more chances and avoid him having to work so hard.
"He holds the ball up brilliantly but if we keep the ball better ourselves and create him a few more chances, he'll score more goals."
McCarthy admits he is anxiously awaiting news over the fitness of midfield duo Adlene Guedioura (ankle) and Dave Edwards (back).
He said: "I'm happy with my squad but if I lose two midfield players, that would put a serious dent in it."