The vaccination requirement was initially set to kick in on Monday and remain in effect at least until the end of January.
However, Anutin Charnvirakul told reporters proof of vaccination was not needed as there was sufficient immunization globally, while those not vaccinated would be granted entry without restriction.
Anutin's announcement replaced the requirements announced on Saturday by the Civil Aviation Authority of Thailand. The rules had said that all foreign arrivals would have to prove they are vaccinated or provide a letter certifying that they have recovered from Covid-19 within six months.
The announcement by the aviation regulator came ahead of China reopening its borders on Sunday.