A tour speedboat collided with a trawler near Koh Khai-Koh Phi Phi in Krabi province on Sunday injuring 22 people, one of whom later died.
The speedboat, which overturned, was carrying 55 people, including a crew of three.
The collision occurred about 8.55am in the Andaman Sea between Koh Khai and Koh Phi Phi.
Two rescue boats were rushed to the scene to take the tourists and crew to safety.
According to the regional marine office in nearby Phuket, the speedboat was carrying three boat crew, two guides and 50 tourists who were mostly Russians. The fishing vessel was the Pichaisamut 1.
Twenty-two people were injure - three Thais and 19 foreigners. One of them was in critical condition and later died. She was a Russian tourist, identified as Starykh Elizaveta.
They were all put ashore at Chalong Pier in Phuket and were rushed to medical treatment.
