Walker made 15 appearances in the first half of last season for City before joining AC Milan on loan in January, but the Italian club decided not to make his move permanent.
He won 17 trophies during his time at Etihad Stadium and was part of the squad that won the Treble in 2023.
Walker, who started his career at Sheffield United, signed for City in the summer of 2017 for an initial £45m and made 319 appearances for the club.
Burnley were promoted back to the Premier League last season following their relegation in 2024.
The Clarets creatively announced Walker’s arrival on X, , externalusing Popstar Lionel Richie’s music video for his song ‘Hello’.
Walker is their fifth signing of the summer, following the arrival of defender Axel Tuanzebe, left-back Quilindschy Hartman, goalkeeper Max Weiss and French winger Loum Tchaouna.
Check out all the summer transfer deals on our dedicated page.
