Born in Goodmayes, London, Maitland-Niles is a product of Arsenal's Hale End Academy having joined the club at the age of 6.
Maitland-Niles made the step up to Arsenal's U21s during the 2013–14 season, having broken into the U18 set up the season before.
He signed his first professional contract with Arsenal on 24 October 2014.

On 9 December 2014, Maitland-Niles made his professional debut at the age of 17 years and 102 days in a UEFA Champions League match against Galatasaray, replacing Aaron Ramsey at half time in an eventual 4–1 win for Arsenal.
In doing so he became the second youngest player to have represented Arsenal in the Champions League, behind Jack Wilshere.
Four days later, he made his Premier League debut, replacing Alex Oxlade-Chamberlain in added time in a 4–1 win against Newcastle United.
Born in Goodmayes, London, Maitland-Niles is a product of Arsenal's Hale End Academy having joined the club at the age of 6. Maitland-Niles made the step up to Arsenal's U21s during the 2013–14 season, having broken into the U18 set up the season before. He signed his first professional contract with Arsenal on 24 October 2014.
On 9 December 2014, Maitland-Niles made his professional debut at the age of 17 years and 102 days in a UEFA Champions League match against Galatasaray, replacing Aaron Ramsey at half time in an eventual 4–1 win for Arsenal. In doing so he became the second youngest player to have represented Arsenal in the Champions League, behind Jack Wilshere. Four days later, he made his Premier League debut, replacing Alex Oxlade-Chamberlain in added time in a 4–1 win against Newcastle United.
Ainsley Maitland-Niles