The left handed India star waded into the weak South attack with gusto and slammed 16 fours and three sixes in his 124 to lift North past their opponents' modest total of 212 for 9 with eight overs to spare.
Yuvraj and seasoned campaigner Ajay Jadeja, who made 34, strung together a vital stand of 122 runs for the fifth wicket to rescue North from a precarious 38 for four, including the wicket of captain Dinesh Mongia (19).
By the time the two were separated at 160 their team was well on way to regaining the title after a one-season gap.
Yuvraj and Sangram Singh (16) then carried the score past 200 with another important stand of 47 runs to put North well in sight of the title-triumph.
Earlier, South struggled against the varied North attack after choosing to bat first and were indebted to opener Dinesh Karthik's 46, Vengopal Rao's 59 and Sridharan Sriram's 36 for their decent score.
North's most successful bowler was off spinner Harbhajan Singh who took 4 for 48 after Amit Bhandari had given early breakthroughs with the wickets of opener Rowland Barrington and South captain Venkata Sai Laxman. Bhandari picked up 2 for 30 in 10 overs.
North finished on top of the league with 14 points while West, who lost by 12 runs to Central at Jamnagar on Friday, finished runners-up with 9 points, followed by Central (8), South (7) and East (2) in that order.