O'Driscoll has made 18 appearances for the Lions, scoring 45 points along the way, and he has appeared in eight Tests for the tourists.
For Ireland, he has won 125 caps, scoring 46 tries in the process and after one more campaign with the Men in Green, and with Leinster, he will hang up his boots.
"This is the 'one more year', I had to think long and hard [about playing this season] and there were a number of factors," O'Driscoll, who signed a new one-year contract with the Irish Rugby Football Union and Leinster earlier this year, confirmed on Newstalk.
"I had to talk to [my wife] Amy [Huberman] and listen to my body, I had to learn if I was still wanted in the Leinster setup and the Irish setup.
"It would be rude of me not to mention the chants from the stands in the RDS of 'one more year', the fact that you're still wanted by the faithful does mean an awful lot too.
"I remember I had a neck operation after the World Cup in 2011 and there was talk at the time that I might not get back playing from it and it started to hit home.
"I've been a professional rugby player all my life, I don't really know anything different.
"I don't really know the big bad world that regular people see and I have been in the process, over the last couple of years, of getting involved in things I'm interested in but nothing will replace the feeling of running out on the pitch but something that makes you get up in the morning and have purpose."