Hamilton posted a time of 1 minute 25.290 seconds, just 0.038 seconds faster than McLaren teammate Jenson Button. Alonso was third, 0.058 seconds behind Hamilton, but struggled with his car in both sessions.
After a suspected engine failure six minutes from the end of the morning session, Alonso had a brake problem halfway through the afternoon outing.
The Spaniard eventually returned to the track, only to encounter another technical problem with his car 25 minutes from the end of the session.
Michael Schumacher was fastest in first practice, posting a time of 1:25.422. The Mercedes driver was 10th in the afternoon.