The win was set up by a Jacques Kallis half-century which helped the home side to 163 for four and then a miserly spell of left-arm spin attack from Iqbal Abdulla, who picked up three wickets for 24 saw them restrict the Chargers to 154 for eight.
Kallis became the highest run-getter in the tournament and completed his wonderful outing by taking four catches.
"We were steady throughout, a good performance in the end. We have a powerful batting line-up and look to set the platform for the big hitters down the order," Kallis said.
Batting first after winning the toss, the Knight Riders reached 50 off 47 balls with the help of a flurry of boundaries from Kallis and Manvinder Bisla.
Spinners pulled things back briefly as Bisla (19 off 21) was trapped lbw Amit Mishra.
Kallis soon brought up his fifty off just 43 balls with a six off Jean-Paul Duminy, but the spinner had his revenge when he dismissed the all-rounder in the next ball.
Gautam Gambhir and Manoj Tiwary then added 43 off 4.3 overs before Mishra struck, removing the home captain who made 29 off 18 balls.
Yusuf Pathan (22 off 15 balls) and Tiwary (30 not out off 21 balls) blasted 31 off the remaining 19 balls to propel the Knight Riders to 163 although Dale Steyn saw off the big hitter with the last ball of the innings.
Abdulla then claimed the wicket of Ishank Jaggi, the Chargers opener who scored three off nine balls, to carry on the momentum.
Eoin Morgan then brilliantly ran out Shikhar Dhawan (seven) but Bharat Chipli and Kumar Sangakkara briefly kept the visitors in the hunt before Rajat Bhatia dismissed the captain for 15-ball 16.
With 84 required off eight overs, new man Duminy tried to take on dangerous Abdulla only to find an agile Kallis at deep midwicket.
Chargers' hopes faded when Chipli fell two runs shy of his half-century to Bhatia (two for 29) but Daniel Christian (25 off 13 balls) gave the home team a scare with a couple of sixes and a boundary, before becoming Abdulla's third victim.
Ravi Teja was snared by Jaidev Unadkat in the next over, which left Steyn and Mishra with a gigantic task. Unadkat's late charge ensured the asking rate remained out of Deccan's reach as they finished at 154 for eight.
Sangakkara said: "I thought 163 was a good total on this wicket. We still got the rate back on track after some early wickets, but kept losing so many wickets."