Of the LA Galaxy star, Wenger told the Daily Mail: "When he was with us, he set an incredible example. He worked and trained like a madman.
"He arrived first in the morning and was last to leave. If I had thought that for a moment he was going to come to us and play the 'big I am' then I never would have allowed him to join my group of players.
"He just brought pleasure to everybody and everybody at Arsenal benefited from him being with us."
Wenger is expected to be in Paris tomorrow night to watch Beckham join the likes of Peter Shilton and Sir Bobby Charlton as an English centurion.
"For me it was natural to welcome him to London Colney to train with us. I thought it would help the whole group of us and give us a boost and it did.
"I had already watched him with the national team when they had used Colney to train and I could tell from that how much he loved his football.
"After training had finished he would stay out there and he and Paul Scholes would just hit long balls and passes to each other for half an hour.
"He never once has given me the impression of being a spoiled child.
"For me he has always looked like somebody who plays football from the heart."