The 21-year-old is particularly looking forward to competing in the Champions League and feels he has the credentials to be a big hit in English football.
Sandro told the club's website: "It is a pleasure to finally be here. I am extremely happy that I have been given the opportunity to join a club like Spurs.
"I cannot wait to get out on to the pitch and show all the fans what I can do. I am determined to make a positive impression on English football and help Spurs move on to a new level.
"Spurs are a team who are talked about a lot in Brazil. They are one of the biggest teams not only in England but also in Europe because of their history.
"I watched every game last season when Spurs were going for fourth place, cheering them on and hoping they would qualify. When they finally did achieve qualification it was an absolutely fantastic moment."
He continued: "The Champions League is the best club competition in the world and I am looking forward to competing at this level. I know Spurs has everything that it takes to go further in the competition and I will do everything I can to help.
"The Premier League is the best league in the world. It is a strong league played at great pace and I think my style of play will adapt quickly to this kind of football."