The attacker left Burnley upon the expiration of his contract at the end of the 2021-22 season and has been a free agent since the summer.
Lennon also represented Tottenham, Leeds United, Everton and Kayserispor during his career, and the former England international now feels that the time is right to call it quits.
"I've finally decided that the time is right to hang up my boots, having weighed up my options I didn't feel any were right for me or for my young family," Lennon wrote on social media.
"It has been a very tough decision as football has been my life since probably the age of three and the last 20 years playing professionally at the top has been so amazing. I've loved every minute of it!
"Football means so much to me and always will do. I don't think I even realised how much until I started considering this retirement, it has been everything and more.
"Now I'm very excited for this next chapter in my life and spending a lot more time with my loved ones. There is so much I want to do and give back with all my experience and my experiences on and off the pitch and will be doing so in the near future.
"Football world, thank you from the bottom of my heart."
Lennon came through the youth ranks at Leeds, scoring once and setting up four more goals in 43 appearances for the Whites as a teenager before joining Spurs in the summer of 2005.
It was at White Hart Lane where Lennon made a name for himself, immediately breaking into the first team at 18 years old and winning the EFL Cup in the 2007-08 campaign.
Lennon spent 10 years at Tottenham, scoring 30 goals and setting up 79 more in 364 appearances across all tournaments and competing for the Lilywhites in the Champions League.
The Englishman was loaned to Everton for the second half of the 2014-15 season before joining the Toffees permanently that summer, spending three and a half years at Goodison Park ahead of a move to Burnley in January 2018.
Lennon initially spent just two and a half years at Turf Moor, joining Kayserispor in Turkey for the 2020-21 season and producing five assists in 36 games before returning to Burnley.
The attacker's final season saw him score two goals in 28 Premier League appearances for the Clarets, but he was unable to prevent them from suffering demotion to the Championship.
In total, Lennon made 416 appearances in the Premier League during his lengthy career, scoring 36 goals and setting up 64 more, and he earned 21 caps for England.
The 35-year-old played at the 2006 and 2010 World Cups for the Three Lions and provided six assists in an England shirt, but he never scored a senior international goal for his country.