"He (Henry) is not a cheat, I know him well," the former France playmaker, who was sent off for head-butting Italy defender Marco Materazzi in the 2006 World Cup final, told French television channel Canal Plus.
"He will get over this," Zidane added. "He made a mistake, like I made a mistake, even if I'm not making any comparisons. We all make mistakes."
Henry, Zidane said, had apoligised by admitting he had handled the ball.
"The fact he said there was a handball means he has apologised," Zidane said. "I'm not saying it was nothing but it was handball, that's it."
France captain Henry handled the ball setting up William Gallas's extra-time equaliser in Wednesday's 1-1 draw in Paris that sent France to the World Cup with a 2-1 aggregate win.
The French Football Federation (FFF) has ruled out a replay, saying world governing body FIFA's decision that the result should stand was final.
Neville defends Henry over handball
Manchester United defender Gary Neville said it was wrong to brand France striker Thierry Henry a cheat for handling the ball in his side's controversial World Cup qualifying playoff victory over Ireland.
"To label Henry a cheat is wrong," Neville wrote in his regular column in Malta's Sunday Times. "Everyone who has played football will know that when the ball comes up at your side, your arm can come out instinctively. We have all done things in football matches in the heat of the moment that we have regretted later. The referee has to spot these things."
FIFA rejected Ireland's request for a replay after Henry's actions helped France to get a 2-1 aggregate win and reach the World Cup finals in South Africa next year.
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