Two more people were confirmed dead on December 6 in the central province of Pathumthani.
Ayutthaya has the highest death toll where 139 people were killed by flood, followed by Nakhon Sawan, where 72 people were killed.
Floods were caused by the heavy monsoon "Nock-Ten" and overflow from several dams in the upper part of the country since mid July.
On December 7, floods still prevail in 11 of the 77 provinces and are affecting about 4.5 million people from 1.6 million households
The floods have affected about 4.1 million households and about 13.6 million people in 64 of the 77 provinces since July 25.
Xinhua