An earthquake measuring 2.2 on the Richter scale was reported on Koh Samui in Surat Thani province on Saturday, following a 2.4-magnitude quake on Thursday.
The Earthquake Observation Division of the Meteorological Department recorded the tremor at 8.31am. Its epicentre was in tambon Bo Put, at a depth of two kilometres.
Surveillance footage captured vibrations in residential areas, with no reports of damage or injury.
A previous earthquake struck Koh Samui on Thursday morning. The Department of Mineral Resources said the quake was caused by the geothermal energy.
Officials have urged people on the southern resort island not to panic over the situation and to follow reports from state agencies. People should move to wide-open spaces or shelter under sturdy structures if another tremor occurs.
One online comment described the latest quake as feeling "like a heavy truck driving by."
Since 2008, there have been 16 earthquakes in Surat Thani. Most occurred on and near the Khlong Marui Fault Zone (KMFZ), a major active strike-slip fault system in southern Thailand.