The German lead from start to finish in an action-packed race and will take the title in Japan next week if he can secure a fifth consecutive win and Fernando Alonso comes lower than eighth.
Both Lotus drivers joined Vettel on the podium, with Kimi Raikkonen finishing in front of his team-mate Romain Grosjean.
Sauber’s Nico Hulkenberg drove the race of his life, fighting off Mercedes’ Lewis Hamilton for fourth place.
Hamilton had passed Hulkenberg on lap 48 but the Sauber driver managed to regain his position with seven laps to go.
There was drama from lap one as five cars abreast approached turn three which saw Ferrari’s Felipe Massa spin, causing damage to Adrian Sutil and Jenson Button, who both had to pit for new front wings.
By lap 13 Vettel had pulled away from the pack and was leading by 2.7 seconds.
There was disappointment for Force India’s Paul Di Resta as he spun off the track on lap 26 and retired for the fourth race in a row.
Nico Rosberg’s race was ruined on lap 28 as his Mercedes’ front nose became loose, causing sparks to fly off his car.
Fortunately, he was able to get his car back to the pits safety but his pit crew struggled to replace the nose, resulting in a 22.6 second stop.
Vettel had created a significant lead but the final 20 laps saw the field close up following two safety-car periods.
Sergio Perez ran wide on lap 31 and his tyre de-laminated, sending debris flying which caused Red Bull’s Mark Webber to suffer a puncture.
Webber’s bad luck continued six laps later when Adrian Sutil spun and hit the Australian which saw the Red Bull burst into flames.
There was confusion as a slow-moving unmarked vehicle joined the track, which was later explained to have been sent by Korean Fire Chiefs to aid Marshals in putting out Webber’s car.
Vettel seemed unaffected by the safety car and was able to pull away on the restart, while Grosjean was urged by Lotus to race his team-mate, Raikkonen.
However, Grosjean was unable to catch up to the Finn and had to settle for third place.
1. Sebastian Vettel Germany Red Bull-Renault 55 laps 1hr 43m 13.701s
2. Kimi Raikkonen Finand Lotus-Renault +00m 04.2s
3. Romain Grosjean France Lotus-Renault +00m 04.9s
4. Nico Hulkenberg Germany Sauber-Ferrari +00m 24.1s
5. Lewis Hamilton Britain Mercedes-Mercedes +00m 25.2s
6. Fernando Alonso Spain Ferrari-Ferrari +00m 26.1s
7. Nico Rosberg Germany Mercedes-Mercedes +00m 26.6s
8. Jenson Button Britain McLaren-Mercedes +00m 32.2s
9. Felipe Massa Brazil Ferrari-Ferrari +00m 34.3s
10. Sergio Perez Mexico McLaren-Mercedes +00m 35.1s
11. Esteban Gutierrez Spain Sauber-Ferrari +00m 35.9s
12. Valtteri Bottas Finland Williams-Renault +00m 47.0s
13. Pastor Maldonado Venezuela Williams-Renault +00m 50.0s
14. Charles Pic France Caterham-Renault +01m 03.5s
15. Jules Bianchi France Marussia-Cosworth +01m 04.5s
16. Giedo van der Garde Holland Caterham-Renault +01m 07.9s
17. Max Chilton Britain Marussia-Cosworth +01m 12.8s
Rtd Jean-Eric Vergne France Toro Rosso-Ferrari 53 laps completed
Rtd Daniel Ricciardo Australia Toro Rosso-Ferrari 52 laps completed
Rtd Adrian Sutil Germany Force India-Mercedes 51 laps completed
Rtd Mark Webber Australia Red Bull-Renault 36 laps completed
Rtd Paul di Resta Britain Force India-Mercedes 24 laps completed
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