The flood is the result of the prolonged heavy rain and high flood tides over recent days.
Local streets have been turned into rivers.
This is also Hoi An's eighth flood since early October, a frequency rarely seen before.
By Wednesday morning, the floodwaters had partially receded but low-lying areas were still affected.
During floods, boats are the main means of transport for people in Hoi An.
Dinh Van Toan from Minh An Ward said that never before had he witnessed floods as frequently as this year.
Tourism in the town had only reopened in early September after a pause due to the second Covid-19 outbreak that hit Vietnam in late July.
