"Denilson's contribution to the club last season was outstanding," said Wenger.
"His work rate really was exceptional and it is valuable to have players that we know will perform to the very last minute in such a demanding league."
Bendtner, who is yet to score this season, will be expected to establish himself as a first-team regular at the Emirates Stadium after Wenger sold first-choice forward Emmanuel Adebayor to Manchester City this summer.
"It's not just about the goals, his all round contribution has improved and will continue to do so," said Wenger.
"Nicklas has impressed me highly with his application and determination over the last season, you can see that he wants to compete at the highest level and win things with his team-mates."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.