Kenny, 29, who is tied with Chris Hoy in Great Britain's individual gold medal count, will mark his return to racing in the Revolution Series at Manchester's HSBC UK National Cycling Centre on January 6.
"To be honest, after Rio, I'd pretty much made my decision to walk away from cycling," Kenny said, according to a press release sent out today from British Cycling.
"But after taking a year out, getting married and having our first child, I felt refreshed. Before I knew it, I was training again. I feel like I'm 18 and starting all over again. Competing at Revolution in January will be the first step on the path to Tokyo."
After Rio, Kenny married Laura Trott, who gave birth to the couple's first child last month.
Another gold in Tokyo would put Kenny ahead of Hoy, while two more medals – including silver or bronze – would make him Great Britain's most decorated Olympian of all time, moving him to nine ahead of Bradley Wiggins.
"Tokyo is a long way off at the moment, and I've never really been motivated by records," Kenny said. "I've just always tried to be the fastest and best I can be. Having said that, to win more gold medals than any other British Olympian would be an amazing achievement."
Great Britain Cycling Team performance director Stephen Park was obviously excited to have a star rider back in the fold.
"Jason's career and record at the Olympic Games speak for themselves, and the fact that he is now targeting a fourth Games is excellent news not just for him as an individual, but for the entire team and in particular the developing riders who can only benefit from his considerable experience over the course of this Olympic cycle," Park said.
"As Britain's joint most-successful Olympian, Jason clearly has a particular goal in his sights over the next three years, and this, coupled with the fantastic strength in depth of our track squad, are sure to make for an exciting few years between now and Tokyo 2020."