Lewis Hamilton continued his form from last week's German Grand Prix to post the fastest lap time of the first practice session at the Hungaroring.
Hamilton was 0.214 seconds ahead of current world champion and this year's championship leader Sebastian Vettel as he posted a time of one minute 23.350 seconds.
Vettel's Red Bull teammate Mark Webber was fourth, with Fernando Alonso of Ferrari third and Hamilton's compatriot and teammate Jenson Button fifth fastest.
The top five drivers were covered by less than half a second, suggesting another tight race in Hungary after the close-fought contest at the Nurburgring on Sunday.
German Vettel, 24, currently leads this year's championship by 77 points ahead of Australian Webber.