The Serie A side have reportedly placed a £52.7 million [€60 million] valuation on Sandro, of which the Red Devils are not willing to pay.
The left-sided defender originally joined Juventus from Porto back in August 2016 for £22.8 million [€26 million] and has just two years on his contract at the club.
Left-back has been a position of problem for Jose Mourinho at Manchester United, with Luke Shaw unable to hold down a spot, forcing Ashley Young back into contention.
Despite a solid season from Young, hes now 32 and Mourinho will be looking towards the future and a player who can make the position permanently his for many seasons to come.
Sandro, at 27 years old, fits the bill but the Portuguese manager faces a fight to acquire his services for a price that the Premier League club feel is fair.
Mourinho has already brought in midfielder Fred and defender Diogo Dalot this summer but hes still looking for further reinforcements at the back.