The Miss Beauty Queen Vietnam contest drew widespread criticism after one contestant - who missed out on the top prize and was unhappy with her lesser title of "Miss Beautiful Body" - posted photos online of her sash dumped in a bin, newspaper Tuoi Tre reported.
The newspaper said the organisers also were fined $2,400 for holding the event without official permission.
"Everyone in the audience and well-known people in the entertainment sector present at the show knew who really deserved to get the beauty queen title," Tran Ngoc Bich, 20, wrote on her Facebook page.
Reports quoted designer Nguyen Huy, a member of the judging panel, as saying that Ms Bich deserved the top prize, but that the final decision was made by the organizers, B-Beauties Magazines.
Another competitor accused one of the organizers of offering her the title of beauty queen in exchange for $17,000, online newspaper VietnamNet said.
Winning beauty contests in Vietnam can lead to contracts with modelling agencies and roles in advertising campaigns. The contest was held May 23-July 13 in Hanoi with 31 contestants.