The 21-year-old scored 14 goals in 31 La Liga games last season, something which is said to have aroused the attention of the Bernabeu-based giants.
According to 'Marca', Real are looking to strengthen their attack ahead of next season, with question marks remaining over both Alvaro Morata and Cristiano Ronaldo's futures and the impending departure of Mariano Diaz to Lyon.
As we reported earlier today, Borja Mayoral looks set to be promoted into the first team squad next season but Sandro's La Liga experience would be a big plus.
The forward has been heavily linked with a move to Everton by the Engish press, but whilst they are said to have met the player's €6m release clause, he is yet to sign on the dotted line. Leaving to door open for Real to swoop.
Atletico Madrid have also been linked with a move for the striker but their situation is complicated due to their ban on registering new players.