Katy Perry remains at two with 'I Kissed A Girl', while Pussycat Dolls bounce back to three with 'When I Grow Up'.
Meanwhile, McFly climb from 23 to four with 'Lies' to score their 15th top ten hit. Gym Class Heroes also enter the top ten this week, jumping from 12 to six with 'Cookie Jar'.
The highest new entry of the week comes from Will Young, who debuts at ten with 'Changes', his first single since April 2006.
Oscar winner Jennifer Hudson scores the second highest new entry, entering at 15 with 'Spotlight'.
The top ten in full (click for our reviews):
1. (1) Kings Of Leon: 'Sex On Fire'
2. (2) Katy Perry: 'I Kissed A Girl'
3. (4) Pussycat Dolls: 'When I Grow Up'
4. (23) McFly: 'Lies'
5. (5) Rihanna: 'Disturbia'
6. (12) Gym Class Heroes ft. The Dream: 'Cookie Jar'
7. (8) Madcon: 'Beggin'
8. (7) The Script: 'The Man Who Can't Be Moved'
9. (14) Ne-Yo: 'Miss Independent'
10. (-) Will Young: 'Changes'
> Click here for this week's UK albums chart