Manchester City captain Walker spent eight years at Spurs between 2009-2017 and spoke about his former manager on his podcast and how much he meant to the squad.
He said he will "never, ever forget" when Villas-Boas addressed the squad after his sacking and spoke about how other teammates broke down in tears.
"I've got tears running down my eyes... Michael Dawson is welling up," said the 34-year-old. "That's how much he meant to the lads."
The Portuguese manager almost led Spurs to the Champions League in his first season with a squad that included 2012-13 PFA Player of the Year, Gareth Bale.
The manager was let go after a 5-0 defeat by Liverpool in December 2013 and Walker admitted he regrets the team's poor performances that led to his departure.
"(The team) Didn't do him justice. For 10 or 12 men to be crying because the manager's gone, he's done something well in the dressing room."