Raina, 27, struck six fours and eight sixes in his 62-ball innings as the Super Kings chased a target of 181 with nine balls to spare in Bangalore.
Left-arm spinner Pawan Negi took 5-22 as Indian Premier League champions Kolkata were restricted to 180-6.
The win secured fellow IPL side Chennai their second Champions League title.
Gautam Gambhir (80) and Robin Uthappa (39) had earlier shared a 91-run opening partnership for Kolkata after they had lost the toss and been asked to bat.
But, Negi soon got on top of the batting and restricted the Knight Riders, picking up Utappa's wicket, as well as those of Jacques Kallis, Ryan ten Doeschate, Manish Pandey and Suryakumar Yadav.
Coming in at number three following the early loss of West Indian Dwayne Smith, India batsman Raina then set about dominating the Kolkata bowlers.
He was initially supported by New Zealand batsman Brendon McCullum (39) in a second-wicket partnership of 118.
Raina reached his century off 59 balls and India captain Mahendra Dhoni joined him at the fall of the second wicket to hit a run-a-ball 23 to help his side to victory.
Suresh Raina powered Chennai Super Kings to an eight-wicket win over Kolkata Knight Riders in the Champions League final with an unbeaten 109.