The dead person was a woman with cancer and dyslipidemia, who had lived in Samut Sakhon province, and had tested positive on February 19 died on March 12.
Of 11 overseas travellers found positive in state quarantine, four were Thais from Bangladesh.
The others were citizens of Sri Lanka, the US, the UK, Afghanistan, Poland, Nigeria, and Zimbabwe from their respective countries.
Separately, 30 patients have recovered and been discharged.
As of Saturday, the number of confirmed cases in Thailand had risen to 26,757. Of these, 23,844 had been infected locally, including 14,829 who were found via proactive testing, while 2,913 were returnees. So far, 26,086 have recovered and been discharged, 585 patients are still in hospitals, and 86 have died.
According to Worldometer, as of 10am on Saturday, the number of confirmed cases globally had risen to 119.6 million (up by 488,414), 96.25 million have recovered, 20.7 million are active cases (89,376 in severe condition) and 2.65 million have died (up by 9,361).
Thailand ranks 116th on the global list of most cases, which is topped by the US with 29.99 million, followed by India at 11.36 million, Brazil 11.33 million, Russia 4.37 million and the United Kingdom 4.24 million.