The accident happened at the Venetian Catering Hall in Garfield on Friday night.
Police say the DJ brought a carbon dioxide canister to use for special effects. The canister burst without warning and injured two men and a woman on the dance floor.
The victims, all in their thirties, were taken to the hospital with non-life-threatening injuries.
The wedding was stalled. The Venetian did not sustain significant damage.
Authorities are still investigating the cause of the explosion.