Soderling had 20 aces and Roddick had 22 in a match that had no breaks.
Roddick has been trying to qualify for next month's Masters Cup in Shanghai. Three of the eight berths are open.
Soderling will next face fourth-seeded Gilles Simon of France, who ousted Josselin Ouanna 6-3, 7-5.
Roddick advances at Lyon Grand Prix
Ballon d’Or Nominees Announced
Roddick reaches Lyon GP quarterfinals
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