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.