The tickets, which used to cost VND250,000 ($10.86) a person, have been waived until year-end.
The tourism industry in Quang Ninh, home to the UNESCO heritage site and beautiful beaches, has been hit hard by the Covid-19 crisis with hundreds of cruise ships remaining anchored for long due in the absence of visitors.
After more than a month without new cases, Quang Ninh lifted the swimming ban and reopened tourist destinations, relics, historical sites, and golf courses on June 8, but still prohibits visitors from outside.
According to the Ha Long Bay management board, the world-famous bay has only been receiving 30-50 visitors a day for the last 10 days, and cruise ships are still not ready to resume operations due to lack of demand.
Last week the owners of 500 cruise ships submitted a petition to the government for support saying they are on verge of bankruptcy.
The number of visitors to Quang Ninh fell by 37 percent last year to 8.8 million as Vietnam closed its borders from March 2020 to keep out Covid.
Revenues from ticket sales in Ha Long Bay plunged by VND1 trillion ($43.47 million) last year and over 5,000 tourism workers lost their jobs.
Since its recognition as a UNESCO natural world heritage in 1994, Ha Long Bay has found a spot on the global tourism map, with travel bloggers and filmmakers hailing its emerald waters and thousands of towering limestone pillars topped by rainforests.