Ferdinand agreed a two-year contract with Nigel Adkins' team following his departure from Turkish side Antalyaspor.
The 29-year-old, whose brother is QPR's Rio Ferdinand, quit English football following the controversy that saw Chelsea star John Terry accused of racially abusing him.
Terry was found not guilty when the case went to Westminster Magistrates Court, but the Football Association later banned him for four matches and he was also stripped of the England captaincy.
However, Ferdinand wasn't fulfilled by his time in Turkey, where he also played for Bursaspor on loan, and the former West Ham and Sunderland centre-back admitted he was relieved to return to England.
"I've been away from English football for a year and had some tough times
Turkey is a fantastic place to go and play football, but certain things off the field didn't allow me to enjoy my football," Ferdinand told Reading's website.
"That chapter is closed now, and I've opened a new chapter at Reading and I'm looking forward to it.
"I've got things to prove, to myself and everyone
A lot of people have written me off and doubted me because I've been away for a year, but I'm here to prove to people that I can offer a lot to English football.
"I want to offer what I can to Reading, and hopefully that means promotion."
Source : AFP