Sexton suggested earlier this week that he will see out his contract with Racing Metro in France but Schmidt, who guided Ireland to the Six Nations title last weekend, refused to hide his preference when quizzed about the matter.
"It would be great to have Johnny back in the country," Schmidt told reporters. "I don't think I've ever made any debate of that.
"To be honest the talk is outside anything that we've done right now. If there's a chance of it happening I'd be delighted.
"If Johnny were to come back it would be great, but one of the problems with that is that Johnny is pretty much a man of his word."
Sexton joined Racing Metro from Leinster in January 2013.