The 1.335 kg of drugs were seized by the Airport Interdiction Task Force (AITF) under the Office of the Narcotics Control Board (ONCB).
ONCB Secretary-General Wichai Chaimongkhon explained that 490 grams of methamphetamine were found inside an orange pillow among monk supplies, while 845 grams were found among heat patches.
He said the AITF would send the confiscated parcels to the Narcotics Suppression Bureau for legal action.
"The ONCB also has sent information on the addressee to the Australian Federal Police," he said.
He added that the crackdown was in line with Deputy Prime Minister General Prawit Wongsuwan's order on preventing drug trafficking, as it may affect the country's reputation.
"This move is also in line with Justice Minister Somsak Thepsuthin's order to strictly monitor drug trafficking via parcels to several countries, especially Australia, New Zealand, Japan and Korea," he added.