Casey Stoner maintained his record of topping every session in the Losail MotoGP weekend as he also led the pre-race warm-up.
Valentino Rossi briefly deposed his main rival, but Stoner was soon back on top with a lap of 1m55.530s, 0.4secclear of the champion.
Jorge Lorenzo was third on the second Yamaha, ahead of Stoner's Ducati teammate Nicky Hayden. Ben Spies improved on his qualifying form to complete the top five for Tech 3 Yamaha, while LCR's Randy de Puniet was again the top Honda rider in sixth.
The session saw two crashes, with Suzuki's Alvaro Bautista and Pramac Ducati's Mika Kallio both falling without injury.
Pos Rider Team Time Gap
1. Casey Stoner Ducati 1m55.530s
2. Valentino Rossi Yamaha 1m55.968s + 0.438s
3. Jorge Lorenzo Yamaha 1m56.387s + 0.857s
4. Nicky Hayden Ducati 1m56.583s + 1.053s
5. Ben Spies Tech 3 Yamaha 1m56.871s + 1.341s
6. Randy de Puniet LCR Honda 1m56.904s + 1.374s
7. Andrea Dovizioso Honda 1m56.931s + 1.401s
8. Dani Pedrosa Honda 1m57.004s + 1.474s
9. Colin Edwards Tech 3 Yamaha 1m57.139s + 1.609s
10. Loris Capirossi Suzuki 1m57.350s + 1.820s
11. Hector Barbera Aspar Ducati 1m57.357s + 1.827s
12. Aleix Espargaro Pramac Ducati 1m57.435s + 1.905s
13. Marco Melandri Gresini Honda 1m57.528s + 1.998s
14. Hiroshi Aoyama Interwetten Honda 1m57.540s + 2.100s
15. Marco Simoncelli Gresini Honda 1m57.654s + 2.124s
16. Alvaro Bautista Suzuki 1m57.682s + 2.152s
17. Mika Kallio Pramac Ducati 1m57.977s + 2.447s