Aymeric Laporte headed home from close range following a corner after 33 minutes and then on the hour Aduriz found Markel Susaeta to slot in.
Aduriz wrapped up the win with a clinical finish after being played in by Raul Garcia with 68 minutes gone.
Despite plenty of investment, Valencia lie ninth on nine points while Athletic, who have also made a below par start to the season, are 13th with seven points.
Real Madrid’s Cristiano Ronaldo has his sight set on breaking the club’s all-time scoring record when they take on Atletico Madrid later on Sunday. He jointly holds the record of 323 goals with Raul.
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Real are fourth on 14 points, two more than Atletico, and a point behind Barcelona who lost away to Sevilla on Saturday.
Villarreal lead on 16 points and take on Levante later.
(Reporting by Tim Hanlon in Barcelona, editing by Alan Baldwin)
