Videos widely shared on social media show dancers from Bistro Fou in the Bai Chay tourist area wearing skimpy clothes and performing suggestive moves outdoors.
Authorities have described them as "offensive" and going "against moral standards and traditional customs."
The videos sparked public criticism of Ha Long’s reputation.
Bistro Fou is a large outdoor bar popular among locals and tourists.
According to the city people's committee, the number of visitors to Ha Long has increased recently to 40,000-60,000 a day and over 70,000 during weekends.
But recently there have been complaints about scams targeting tourists and overflowing garbage.