A judge has issued a stern warning to a group of laughing protesters in the Wellington District Court.

Twenty-six people have appeared, facing a range of charges after attempting to block participants entering a weapons conference in Wellington last November.

The group sat in the public gallery while members were called into the dock, and laughed and clapped at hearing five people wouldn't qualify for diversion.

It prompted Judge Peter Hobbs to tell the group he "won't have (his) court turned into a laughing matter".

He'd already told court staff the protesters would be "dreaming" if they wanted to continue protesting in the courtroom.

Twenty people will be considered for diversion next month, when the five that don't qualify will also reappear.

The remaining person, Eliana Darroch, pleaded guilty to disorderly behaviour and was convicted and fined $200.