Kwabena Dwamena, 35, was apprehended Monday afternoon on arrival at Suvarnabhumi Airport with 60 packages of crystal meth, weighing one kilogramme, in his stomach, Rakob Srisupa-at, director of the Investigation and Suppression Bureau, told a news briefing on Tuesday.
Mr Dwamena flew Ethiopian Airlines from Ghana to Thailand.
As the man behaved suspiciously after disembarking, customs officers asked him for a body X-ray scan inspection when unidentified objects were detected in his stomach.
After the defecation, 60 packages of crystal meth were found.
The suspect said he swallowed the packages before leaving the Ghanaian capital of Accra for Thailand, adding that he was hired for Bt45,000 (around $1,500) to carry the drugs.
Initially, he was transferred to the police Narcotics Suppression Bureau for further investigation and legal proceedings.
Meanwhile in Pathum Thani province, Soontorn Sawangwong, 36, was arrested with 180,000 methamphetamine pills, worth Bt40 million (more than $1.33 million), at a department store in Thanyaburi district while waiting to deliver the drug to his agent.
The pills were hidden in the car's loudspeaker enclosure, Pol Maj-Gen Piya Sorntrakul, deputy commissioner of Provincial Police Region 1, and Pol Maj-Gen Smith Mukdasanit, Pathum Thani police chief, told a news briefing on Tuesday.
Mr Soontorn said that he was asked to deliver drugs to customers in Pathum Thani, Samut Prakan and nearby provinces six times.