The Spanish Under 21 international has joined The Reds on a season-long loan from Norwich, taking the Club’s tally of close season signings to six.
The former Liverpool man endured a frustrating first season with Norwich after sustaining a serious knee injury.
He made 10 league and cup appearances last term for The Canaries but is hoping for more regular exposure to match action on Trentside.
Ayala told Forest Player: “I’m really looking forward to starting to play and starting to train with the other lads.
“I found out about Forest’s interest about three days ago when Norwich told me I wasn’t going to be playing too much, so I decided the best thing to do was go on loan and play football.
“I was a little bit disappointed at first because I want to play in the Premier League but I know how big a club Forest is and I’m looking forward to playing for them.”
Ayala rose to prominence through the youth ranks at Selvilla but opted to join Liverpool in 2007 instead of signing a professional contact in his home country.
He adds: “I was only 16 and to be honest it was quite difficult to leave my family and friends but I knew what I wanted to do and I’ve no regrets.”