On Thursday, the Gunners unveiled a new Adidas home shirt, ahead of their final game of the Premier League against Watford on Sunday.
Saka has enjoyed a breakthrough campaign at the Emirates this season, making 38 appearances and scoring four times.
The 18-year-old has also registered more assists (11) than any other of his team-mates.
Saka has also shown his versatility in playing at left-back, wing-back, left wing and central midfield.
Now, Saka will forego the No.77 he has been wearing and will take up the No.7 shirt.
Incoming French defender, William Saliba, has also had his shirt number for next season confirmed too.
The centre-back, returning after a season-long loan deal at Saint Etienne, will wear the No.4 shirt.
Mohamed Elneny, the previous owner of the No.4, will revert to No.25.