The tourist boat, named Krakenian The Private of Pattaya, capsized in heavy seas about two kilometres from Pattaya city on Monday evening.
Fortunately, the tourist boat-restaurant was closed at the time due to bad weather, and no injuries or deaths were reported from the sinking.
Prachyaporn Ploymukda, the boat owner, told reporters on Monday night that the boat had succumbed to strong winds and high waves in the Gulf of Thailand.
"The rear part of raft boat sank after being swamped by waves," she said.
The boat has operated as a pirate-themed restaurant since December, with capacity for about 100 customers, she added.
"The boat also offers squid fishing, music shows and karaoke rooms," Prachyaporn said.
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