Manchester United's enquiry, revealed by Spanish outlet AS, comes after Liverpool held talks with the player's agent, Jorge Mendes, for several days before deciding the numbers involved no longer worked.
Liverpool were exploring parallel deals for Mbaye and Bradley Barcola, but Fabrizio Romano reported that PSG's valuation of both players together would mean spending close to €200m, a package Liverpool were not prepared to commit to in full.
Mbaye scored three goals and added two assists in 24 Ligue 1 appearances last season, ten of them starts, establishing himself as one of the most exciting teenage talents in French football under Luis Enrique.
The Senegal international, who has two years left on his contract in Paris, is pushing for a move that would guarantee him regular first-team football rather than a squad role behind PSG's senior forwards.
PSG are believed to want more than €50m for the winger, and the level of interest reflects that valuation: alongside Manchester United, AS reports contact from Bayern Munich, Borussia Dortmund, RB Leipzig, Bayer Leverkusen, Roma, Porto and Aston Villa, with Liverpool still monitoring the situation despite stepping back from an immediate move.
Manchester United's interest is notable given the club's existing options on the right flank, with Amad Diallo and Bryan Mbeumo both currently first-choice under Michael Carrick, and the impending return of Marcus Rashford from his own break potentially complicating minutes further.
Mbaye's rise has been rapid. Born in the Paris suburb of Trappes — also the hometown of former PSG striker Nicolas Anelka — he only began playing organised football at five, having initially been drawn more to basketball, before progressing through Guyancourt and FC Versailles and catching PSG's attention at the age of ten.
He signed his first professional contract in February 2025 despite interest from several of Europe's leading clubs even then, and made his major tournament debut for Senegal at this year's World Cup, scoring once in four appearances as they reached the last 16.
PSG, who won both the Champions League and Ligue 1 last season, are not desperate to sell but have shown willingness to do business at the right price, having already sanctioned Ferran Torres's arrival from Barcelona as a senior addition to their forward line.
Any departure for Mbaye would represent a notable show of faith from a buying club, given how highly PSG themselves still rate a player some in France have compared to Kylian Mbappé at a similar age.