He received valuable support from Sourav Ganguly (58 not out) as India surpassed Sri Lanka's total of 259-7 with six overs to spare to win the series 2-1 on Saturday. The opening match was abandoned due to rain.
The win gave India a crucial psychological edge going into next month's World Cup in the Caribbean as they will meet Sri Lanka in Group B. Others in the group are Bangladesh and Bermuda, with the top two sides advancing to the next round.
Yuvraj and Ganguly built on Robin Uthappa's quickfire 37-ball 52 to steer their team home with a record 145-run stand for the unfinished fourth wicket in a match reduced to 47-overs-a-side due to a damp outfield.
India's previous best for the fourth wicket against Sri Lanka was 128 between Rahul Dravid and Gautam Gambhir in 2005.
The Indian batsmen eventually overshadowed Sri Lankan Chamara Silva, who slammed an impressive 107 not out for his maiden hundred in one-dayers, although Silva clinched the man-of-the-match prize.
Uthappa and Virender Sehwag (46) exploded with a flurry of boundaries early in the innings to keep pressure on Sri Lanka's bowlers and fielders, racing to 92 off just 12 overs.
Uthappa was the more aggressive, hitting one six and nine fours before being caught by Sanath Jayasuriya off seamer Farveez Maharoof.
Sehwag looked set to complete his half-century when he was run out going for what would have been an easy single. He slowed down near the non-striker's end and wicket-keeper Kumar Sangakkara broke the stumps with a direct-throw.
But there was no respite for Sri Lanka as Yuvraj and Ganguly maintained the tempo with their aggressive knocks. They used their feet remarkably well against spinners, each hitting three sixes.
Yuvraj, returning recently from an injury, flayed the Sri Lankan attack during his 83-ball knock as he went for big shots from the beginning and finished the match with his 11th four.
Ganguly, who had retired hurt in the opening over due to cramps, returned after the fall of the second wicket and went on to play a crucial role. He was named man of the series for scoring two half-centuries in three matches.
Silva had earlier steadied the innings after Sri Lanka's top order floundered against the Indian seam attack on a good batting pitch.
The tourists were struggling at 56-4 after being put in to bat, but middle-order batsman Silva came to his team's rescue with a responsible run-a-ball knock in his first match of the series.
The 27-year-old Silva put on 68 for the fifth wicket with Tillakaratne Dilshan and 64 for the seventh with Maharoof to prop up the innings. Dilshan and Maharoof each contributed 28.
Silva, playing in only his 14th one-day international, reached his century in the last over with a four off seamer Shanthakumar Sreesanth. He struck one six and 12 fours in his well-paced hundred.
Ajit Agarkar had done the early damage, removing Sanath Jayasuriya (22) and skipper Mahela Jayawardene (one) in successive overs. Zaheer Khan and Sreesanth then grabbed one wicket apiece to put Sri Lanka in deep trouble.