Alex Rodriguez has been accused of some late-night Yankee-panky with pop queen Madonna -- but his wife Cynthia isn't at home waiting for him, reports the NY Post, which says that she's in Paris hanging out with rocker Lenny Kravitz!

Reports say Mrs. Rod was spotted outside of the Grammy-winning crooner's Paris pad -- where she's said to have been staying for the past four days, while the Rodriguez tots, Natasha 3 and Ella, 2 mos., are in Miami. So are the reports true? That's a negative, "Extra" has learned. A rep for Lenny tells us, "This is unequivocally 100% not true."

Meanwhile, hubby Alex has endured questions about late night visits with Madonna, while her marriage to Guy Ritchie continues to be the subject of divorce rumors.

A-Rod was notably in trouble with his wife last year, after revelations of travels with stripper Joslyn Morse.