The Gunners made this known on Thursday in their official website.
Maitland-Niles was injured during the first half of the Gunners' opening day defeat against Manchester City.
Arsenal have confirmed that utility midfielder/defender Ainsley Maitland-Niles has suffered a fracture to the fibula bone in his left leg that is likely to rule the 20-year-old out of action for the next six to eight weeks.
Right-back Carl Jenkinson will also be out for up to two months with an ankle sprain, seemingly ruling out the possibility of him being sold before the European transfer window closes.
Arsenal manager Unai Emery is facing a defensive crisis at left-back, with Sead Kolasinac and Ainsley Maitland-Niles injured, while Spain global, Nacho Monreal is still battling to be fit to face Chelsea on Saturday.
And club captain Laurent Koscielny will continue his recovery from Achilles surgery and is aiming to make his comeback in November.
A product of the Arsenal academy, Maitland-Niles broke into the first team last season under Arsene Wenger and has often been used in the wing-back positions despite being a midfielder.
There was, though, also positive news as Arsenal reported left-back Monreal and Danny Welbeck were both in full training, so should come into contention for the trip to Stamford Bridge.
- Look Wallabies front row named to face All Blacks
- Putin dances with Austrian foreign minister at her wedding
- Arsenal FC Goalkeeper David Ospina Set for Napoli Medical, Loan Move
- Nick Foles leaves Eagles' preseason game with shoulder strain
- SEC's Scrutiny of Tesla (NASDAQ:TSLA) and Elon Musk Expands
- Netflix Cancels The Break with Michelle Wolf, Joel McHale Show
- Former UN Secretary General Kofi Annan is dead
- Trump cancels DC military parade; says he will go to Paris instead
- Ohio State Urban Meyer update
- Inter taking legal action against Tebas over Modric transfer comments