Authorities in La Da Commune said emergency crews were working to clear mud, rocks and debris washed onto the highway after prolonged downpours.
The flooding occurred on Saturday afternoon when heavy rain sent water rushing downstream into Da Chos Stream, carrying large amounts of soil and rocks onto a section of National Highway 55 through Da Mi 1 Village.
Floodwaters also entered several homes, damaging household appliances and property, including refrigerators, washing machines and motorbikes.
The affected section of the highway remained blocked at around 9 pm.
Local authorities deployed military and police personnel overnight to clear the debris and help residents recover from the flooding.