Delhi, starting day four at 132 for six, were bowled out for 201 in their second innings, giving their bowlers a meagre 115 to defend.
Karnataka ensured there were no hiccups in the chase, getting past the paltry target in 28.1 overs. Opener Mayank Agarwal remained unbeaten on 68 off 96 balls alongside Manish Pandey (11 off 3).
Karnataka, who had qualified for the quarterfinals prior to the game, topped Group A with 38 points from eight games.
With the loss, Delhi failed to make the knock-out stage for another season ending with 19 points from eight matches. They have not had much success in the premier domestic tournament after winning the title in the 2007-08 season.
The Kotla pitch is known for its low-slow nature but unpredicatbale bounce on the final day made the batting even more trickier.
Varun Sood (0) and Sumit Narwal (21) fell victim to the unpredictable bounce, leaving Delhi tottering at 176 for eight. Milind Kumar (31 not out) provided some resistance and took the team past the 200-mark. Karnataka pacers HS Sharath and Ronit More shared three wickets apiece with leggie Shreyas Gopal.
It seemed like Karnataka were batting on a different strip when they came out for the run chase.
Agarwal made stroke play look easy, hitting six fours and three maximums. Pandey ended the game with a four and a six.
The match also brought an end to a disastrous season for Virender Sehwag, who has scored 234 runs at an average of 19.50.