The Althea Racing rider took his Ducati round the famous German circuit in one minute 56.395 seconds, over a tenth faster than championship hopeful Max Biaggi.
Championship leader Marco Melandri was third fastest, with Britain's Jonathan Rea and Tom Sykes fourth and fifth respectively.
Biaggi trails Melandri by 18.5 points in the title race, with Sykes clinging on to hope a further 22.5 points down, though with three races still to come the British rider remains in the hunt.
Nurburgring FP1 results:
1. Davide Giugliano (Althea Racing) Ducati 1098R 1'56.395
2. Max Biaggi (Aprilia Racing Team) Aprilia RSV4 Factory 1'56.528
3. Marco Melandri (BMW Motorrad Motorsport) BMW S1000 RR 1'56.601
4. Jonathan Rea (Honda World Superbike Team) Honda CBR1000RR 1'56.680
5. Tom Sykes (Kawasaki Racing Team) Kawasaki ZX-10R 1'56.868
6. Sylvain Guintoli (PATA Racing Team) Ducati 1098R 1'57.010
7. Carlos Checa (Althea Racing) Ducati 1098R 1'57.169
8. Leon Camier (FIXI Crescent Suzuki) Suzuki GSX-R1000 1'57.259
9. Leon Haslam (BMW Motorrad Motorsport) BMW S1000 RR 1'57.354
10. Eugene Laverty (Aprilia Racing Team) Aprilia RSV4 Factory 1'57.459
11. Michel Fabrizio (BMW Motorrad Italia GoldBet) BMW S1000 RR 1'57.550
12. Chaz Davies (ParkinGO MTC Racing) Aprilia RSV4 Factory 1'57.642
13. Lorenzo Zanetti (PATA Racing Team) Ducati 1098R 1'57.845
14. Ayrton Badovini (BMW Motorrad Italia GoldBet) BMW S1000 RR 1'58.088
15. Maxime Berger (Team Effenbert Liberty Racing) Ducati 1098R 1'58.104
16. Loris Baz (Kawasaki Racing Team) Kawasaki ZX-10R 1'58.128
17. Niccolò Canepa (Red Devils Roma) Ducati 1098R 1'58.268
18. John Hopkins (FIXI Crescent Suzuki) Suzuki GSX-R1000 1'58.758
19. David Salom (Team Pedercini) Kawasaki ZX-10R 1'59.230
20. Lorenzo Lanzi (Liberty Racing Team Effenbert) Ducati 1098R 1'59.636
21. Hiroshi Aoyama (Honda World Superbike Team) Honda CBR1000RR 1'59.758
22. Alexander Lundh (Team Pedercini) Kawasaki ZX-10R 2'00.937
23. Norino Brignola (Grillini Progea Superbike Team) BMW S1000 RR 2'01.227
24. Brett McCormick (Team Effenbert Liberty Racing) Ducati 1098R 2'01.469
