The Mexico international has been searching for a switch away from White Hart Lane for some time, having endured a hugely frustrating spell in England.
He arrived at Spurs in 2008 with a big reputation, having graduated through the academy ranks at Barcelona.
Dos Santos was, however, unable to hold down a regular first-team role and was forced to look elsewhere for games.
Loan spells at Ipswich, Galatsaray and Racing Santander allowed him to show what he is capable of, but he continued to be overlooked at Tottenham.
The 23-year-old will now get the opportunity to start afresh in 2012/13 after sealing a permanent return to Spanish football.
He becomes the latest creative talent to head for the exits at Tottenham, with Luka Modric, Steven Pienaar and Rafael van der Vaart having been allowed to move on by Andre Villas-Boas.
"Real Mallorca have reached an agreement with Tottenham for Giovani Dos Santos on a contract for the next four seasons," read a statement on Mallorca's official website.