The villages along the Khao Phanom-Chaiyaburi road in Tambon Khao Phanom of Khao Phanom district were flooded at about 7.30pm after the rain started at about 4pm.
The road, which is a main link between Krabi and Surat Thani, was covered by between 30 and 70 centimetres of water.
Dozen of houses in Moo 1 village were under about 40cm of water due to mountain runoff.
Residents said several grocery stores were damaged.