A powerful runner, clinical finisher and accurate goal-kicker, former Fiji powerhouse Nadolo will move to Welford Road ahead of the 2020-21 season.
The prolific Nadolo, who can play on the wing or as a centre, has racked up over 1,000 points in domestic rugby and scored in excess of 150 professional tries.
Tigers head coach Geordan Murphy said after landing the 32-year-old: "It's certainly one to get excited about, no matter who you are.
"He's a star of the international game and a player that crowds all over the world have been able to enjoy see play.
"Now, the Tigers faithful get that chance and the playing squad, as well as coaching staff, get the opportunity to work alongside and with Nemani from next season."
We will welcome Nemani Nadolo to the club ahead of the 2020/21 season.
— Leicester Tigers (@LeicesterTigers) March 2, 2020
England scrum-half Ben Youngs and his older sibling, Tigers captain Tom, will line up with Nadolo next season after committing their futures to the club.
Murphy said: "Ben is Tigers through and through and, for more than a decade, has given everything for the badge.
"To have him recommit is sensational for everyone in Leicester; players, coaches, staff and fans."
He added of the skipper: "Tom is everything you can ask for and more in a club captain.
"His leadership and experience are imperative to what we are building here in Leicester and passion for Tigers is unrivalled."
Photo Getty Images Caption: Leicester Tigers-bound outside-back Nemani Nadolo