Diego Leonardo Chavez, 35, appeared in Auckland District Court this morning where he was found guilty of assault in a reserved decision by Judge David Sharp.
He was remanded on bail until sentencing on February 5.
Chavez was at a protest outside Prime Minister John Key's post-Budget speech at Auckland's SkyCity events centre on May 22.
The court heard evidence earlier this year that Chavez launched himself at Henry and spat at him, hitting him on the neck.
The TV personality said he was confronted by a screaming mob of semi-deranged people as he was on the way to attend a charity lunch.
"It was very threatening, extraordinarily threatening," he has said.
"That's the huge issue for me. It was very aggressive. A couple of them were screaming at me right in my face, literally just standing there right in my face. So the options were reducing and it felt like it was becoming more and more inflamed."
Then, as he was shepherded away, he was attacked.
"From behind, someone spat on me and I was pushed. For me that was the final straw. People have a right to protest and expression is very important and should be upheld. But this was way beyond where people should go," Henry told the court.
