Around half an hour after the party started at a hall belonging to a church, the fire started in the area where a music band was playing.
The band was on the stage that was filled with inflammable materials used for decoration, and the fire spread quickly.
"I was just eating and when I looked up to the stage I saw a small fire. I turned to tell others and when I looked back, it already grew into a big fire. We quickly ran out and as we reached the door, the entire hall had been filled with black smoke and a burning smell," a guest named Son said.
The groom, Ngo Duc Thang, said: "Everybody was scared and many were crying. It was lucky that no one was hurt."
Four fire trucks arrived and put out the blaze in 30 minutes.
Nguyen Duc Vu, chairman of Xuan Son Commune, Chau Duc District, said people managed to escape quickly since the hall is large and has open entrances.
The police suspect an electrical short circuit could have caused the fire.
The damage is estimated at VND1 billion (US$40,850).