They include three Thai returnees from Singapore, two from the United States and one French man from the United Kingdom.
Meanwhile, two patients have recovered and been discharged.
The total number of confirmed cases in Thailand stood at 3,444 (506 in state quarantine), of whom 105 are in hospital and 3,281 have recovered and been discharged. The death toll remains unchanged at 58.
According to Worldometer, as of 10 am on Sunday, the total number of confirmed cases globally passed 27 million. Of the total, 19.1 million have recovered, while 60,719 are in serious condition and 883,707 have died so far.
Thailand ranks 122nd for most cases in the world, while the US has the most number with 6.43 million, followed by Brazil 4.12 million, India 4.11 million, Russia 1 million, and Peru 683,702.