Lukas Podolski set the Gunners on their way with his 14th-minute opener, before Santi Cazorla marked a sparkling display with a hat-trick at the Madejski.
With Arsenal 4-0 up, Reading halved the deficit through Adam Le Fondre and Jimmy Kebe.
But Theo Walcott, deployed as a lone striker by Arsène Wenger, stroked home to add gloss to a win that moves the Gunners up to fifth in the Premier League table.
“It’s been a tough week,” Wilshere told Sky Sports. “It was a disappointing result [at Bradford in the Capital One Cup]. We knew we had to come here and be strong against a strong Reading team.
“We knew they were going to be up for it but we showed great character tonight. Theo [Walcott] and Santi [Cazorla] were a different class.
“We saw the ‘old Arsenal’ tonight in some patches. Obviously we have to tighten up defensively, we gave a few sloppy goals away.
“But it was great with Theo up front and Oxlade-Chamberlain on the wing and we played some of our old stuff tonight. We need to continue that going forward.”
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