Tra Que vegetable village, Thanh Ha pottery village and Cu Lao Cham Island were closed to tourists from Tuesday.
Tourists in Hoi An
Meanwhile, several historical sites in Hoi An Ancient Town have been also closed for being sterilised.
Local authorities have arranged staff to tighten control over Covid-19 quarantine measures for people who leave and come to Cu Lao Cham.
Residents in Cu Lao Cham are advised go to the mainland only in very necessary cases.
Earlier, many other tourist sites in Vietnam such as Cat Ba Island in Haiphong City and Ly Son Island in Quang Ngai Province decided to suspend the welcome of travellers to help Covid-19 virus prevention.