Saka has signed a four-year deal that will run until 2027 and makes him the best-paid player at Arsenal.
The 21-year-old has been in fine form so far this season, scoring 14 goals and laying on 11 assists.
The winger helped the Gunners challenge for the Premier League title, although they ultimately lost out to Manchester City.
Edu is delighted to have agreed terms with Saka, who would have had one year left on his contract this summer, and he believes Arsenal have one of the best young players in the world on their books.
“It has been so enjoyable to work with everyone to extend Bukayo’s contract,” said Edu.
“It is a very proud moment for us all at the club, to work hard with Bukayo and experience his great journey from our academy through to our first team.
“Bukayo has now developed into one of the best young players in the game and we’re looking forward to enjoying together this next stage of his career with us.”